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ISSN: 1511-3701

I V*» I I IA. II I IX KM. \J \S \~* I II U4, I VX I

TROPICALAgricultural Science

VOLUME 23 N0.2SEPTEMBER 2000

A scientific journal published by Universiti Putra Malaysia Press

Pertanika Journal of Tropical Agricultural Science

About the JournalPertanika a leading agricultural journal in Malaysia began

publication in 1978. After 15 years as a multidisciplinary

journal, the revamped Pertanika Journal of Tropical Agricul-

tural Saence will now focus on tropical agricultural research.

The journal will be current and regular, bringing the latest

information related to plant and animal sciences, fisheries,

food sciences and forestry to the attention of researchers and

scientists. It will be published three times a year i.e. in April,

August and December.

Aims and Scope

The journal will accept contributions from managers,

researchers and scientists in the fields of biochemistry,

ecology, genetics, physiology, pathology and management

and production of plants and animals of economic

importance. Pertanika Journal of Tropical Agricultural Science

will consider for publication articles both in English and

Bahasa melayu. Articles must be original reports of research,

not previously or simultaneously published in anv other

scientific or technical journal.

I Submission of ManuscriptThree complete clear copies of the manuscript are to besubmitted to

The Chief EditorPertanika Journal of Tropical Agricultural ScienceIniversiti Putra Malaysia43400 UPM Serdang, Selangor Darul EhsanMALAYSIATel: 89486101 Ext 8854; Fax: (60S) 89433484

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EDITORIAL BOARD

Prof Dr. Tan Soon GuanFaculty of Science and Environmental Studies

Prof. Dr. Khoo Khay ChongFaculty of Agriculture

Prof. Dr. A/izah HashimFacult\ of Agriculture

Assoc. Prof. Dr. Fatimah Vutol

Assoc. Prof. Dr. Abdullah SipatFatuity of Science and Environmental Studies

ASMK Prof. Dr. Khatijah bt. Mohd YusoffFatuity of Science and Environmental Studies

Assoc. Prof. Dr. Ahmad Said SajapFaculty of Foresty

KttOC. Prof. Dr. Sheikh Ali AbodFaculty of Forestry

Assoc. Prof Dr. Yu Swee yeanFaculty of Food Science and biotechnology

Assoc. Prot. Dr. Sheikh Omar Abdul RahmanFatuity oj Veterinary Medicine and AnimalScience

Dr. Zulkitli Idrus

Sumangala Pillai - SecretaryUmversiti Putra Malaysia Press

INTERNATIONAL PANEL MEMBERS

Prof. Sifa LiShanghai Fisheries University

Prof. A.R. EganI nii'ersity of Melboume

Prof. DA. LedwardUmversiti of Reading

Dr. Setijati D. SastrapradjaIndonesian Institute of Sciences

Prof. E.H. RobertsUniversity of Reading

Prof. Dr. Yuan Chung ZeeUniversity of California, Davis

Prof. Tom LovellAuburn University

Prof. E.P. BachelardAustralian Xational University

Prof. V.L. ChopraIndian Council of Agricultural Reasearch

Prof. Ladda A. DushkinaAU Union Institute of MarineFisheries and Oceanography

Richard H. YoungUSCEF, Sew Delhi

Published by L'niversiti Putra Malaysia PressISSN No.: 0128-7680Printed by: Malindo Printers Sdn. Bhd.

ARCHIVE COPY(Please Do Not Remove)


Volume 23 Number 2 (September) 2000

Contents

Effect of Spice Dust on Lung Functions and Respiratory Symptoms in 61Spice Factory Workers in Selangor - Hamdan Noor, Wahidah Sansi,Zolkepli Othman and Faridah Mohamad

Leaf Growth and Stomatal Sensitivity after Water Stress Relief and its 67Relation to Xylem Sap Absicisic Acid - Mohd Razi Ismail and W. JDavies

CEREZ-Maize Simulation Model: Establishment of Planting Windows 75for Grains Maize under Rainfed Conditions - H. Abd. Razak, B. Y.Aminuddin and FL Mohd Fauzi

Effect of Dactylaria higginsii on Purple Nutsedge (Cyperus rotundus) 83Interference with Pepper (Capsium annuum L) - B. Kadir, KCharudattan, WM. Stall and T. A. Bewick

Macronutrients Distribution and Cycling of Pineapple Planted on 89Tropical Peat - O.H. Ahmed, M.KA. Husni, MM. Hanafi, S.R SyedOmar and A.R Anuar

Effects of Food Plants on Development of Spirama Retorta (Lepidorptera: 97Noctuidae) - Ahmad Said Sajap and Abd. Karim Abd. Samad

Quality Assessment of Local and Franchise Beef and Chicken Burgers 103- A.S. Babji, M.N. Nuri, J. Suherman, and M.Y. Seri Chempaka

PertanikaJ. Trop. Agric. Sci. 23(2): 61 - 66 (2000) ISSN: 1511-3701© Universiti Putra Malaysia Press

Effects of Spice Dust on Lung Functions and Respiratory Symptomsin Spice Factory Workers in Selangor

HAMDAN NOOR, WAHIDAH SANSI, ZOLKEPLI OTHMAN and FARIDAH MOHAMADJabatan Biobgi, Fakulti Sains dan Pengajian Alam Sekitar,

Universiti Putra Malaysia43400 UPM Serdang Selangor, Malaysia

Keywords: fine dust (PM10), lung function, vital capacity (VC), forced vital capacity (FVC)

ABSTRAK

Pendedahan kepada habuk rempah telah lama dikaitkan dengan penurunan fungsi paru-paru dan peningkatansimtom-simtom respirasi manusia. Kajian ini telah dijalankan untuk mengkaji kesan pendedahan tersebut keatas fungsi paru-paru dan simtom respirasi di kalangan pekerja-pekerja tiga kilang rempah di Selangor.Pengukuran spirometri (VC, vital capacity; FVC, forced vital capacity; FEV}, forced expiratory volume in 1second) telah dilakukan ke atas 56 pekerja (39 lelaki, 17 wanita), yang terdedah kepada habuk halus, PM]0

sebanyak 2496\ig/m3. Subjek kajian juga mengisi satu set borang soal selidik kesihatan (soal selidik ATS yangdiubahsuai) yang merangkumi simtom-simtom respirasi. 61 subjek dari UPM dipilih sebagai kawalan (36 lelaki,25 wanita), dengan aras dedahan hanya 101\ig/mJ. Kajian mendapati perbezaan yang signifikan bagi VC,FVC dan FEV1 antara subjek kajian dan kawalan bagi kumpulan lelaki dan wanita. Di samping penurunannilai-nilai spirometri, lebih ramai subjek daripada kumpulan pekerja melaporkan kejadian simtom-simtomrespirasi berbanding kawalan. Oleh itu, kajian ini mencadangkan bahawa pendedahan kepada habuk rempahdi kilang-kilang berkenaan membawa kepada periambahan kejadian simtom-simtom respirasi dan penurunanfungsi paru-paru di kalangan pekerja-pekerjanya.

ABSTRACT

Exposure to spice dust has long been associated with increased prevalence of respiratory symptoms and reducedlung function in man. This study was carried out to investigate the effect of such exposure on the workersi lungfunction and respiratory symptoms in three spice-processing factories in Selangor. Spirometry measurements(VC,vital capacity; FVC, forced vital capacity; FEVlf forced expiratory volume in 1 second) xvere performed on 56workers (39 males, 17 females) who were occupationally exposed to 2496\ig/m3 respirable fine dust, PMJ0. Thesubjects also completed a set of standard respiratory questionnaires (modified ATS questionnaires). 61 personsfrom Universiti Putra Malaysia (36 males, 25 females) served as controls. The PMW measurement in UPM wasonly 101fxg/m\ Significant differences in VC, FVC and FEV{ were observed between the two groups for both themale and the female. In addition to the decrease in spirometric values, the workers also reported higher prevalenceof respiratory symptoms compared to controls. Therefore, the study suggests that exposure to spice dust in the spicefactories leads to an increased prevalence of respiratory symptoms and impaired lung function.

INTRODUCTION

As a multi-racial country, Malaysians enjoy avariety of dishes; many are hot and spicy. Oneof the major food ingredients is spice; driedparts of various plants cultivated for their aro-matic and pungent components. The spiceincludes chili pepper, cinnamon, coriander, gin-ger, garlic etc (Zuskin et al. 1988). Because ofthe high demand, spice-processing factories

become one of the major food-processing indus-tries in Malaysia, involving many labourers.

Since the process of spice preparation in-volves grinding, the labourers are constantlyexposed to spice dust. The health of workersexposed to highly dusty environment (especiallyparticles less than 10|u,m) is of serious concernbecause it has been implied that chronic pulmo-nary problems afflict one of every five persons

HAMDAN NOOR, WAHIDAH SANSI, ZOLKEPLI OTHMAN and FARIDAH MOHAMAD

exposed to dust. Such problems include reduc-tions in spirometry values, increases in chesttightness, and also wheezing (U.S. National Re-search Council 1989).

Occupational exposure to spice dust hasbeen reported to cause allergic reactionsmanifested by dermatological, gastrointestinalor neurological symptoms (Zuskin et al. 1988).Adverse effect of the exposure on the respira-tory system has been widely reported elsewhere.Brooks (1985) reported an association betweennumerous spices and occupational asthma. Thespices includes garlic dust (Felleroni et al. 1981),cinnamon (Uragoda 1984), coriander, mace,ginger and paprika (Toorenenbergen and Dieges1985), and buckwheat aerosols (Gohte et al.1983). Fuller et al (1985) reported irritation ofthe airways in relation to inhaled capsicum aero-sols. In terms of other respiratory symptoms,Uragoda (1966) observed a very high incidenceof sneezing, runny nose and cough amongworkers occupationally exposed to chili peppers.Blanc et al. (1991) confirmed the associationbetween the exposure with complaints of cough.A high percentage of upper respiratory tractinfections (URTI) symptoms including sneezingand runny nose was also observed in spicegrinders in Singapore (49.2%) as reported byChan et al (1990).

Despite the above-mentioned evidence, nostudy on this occupational hazard has yet beenreported in Malaysia although there are a largenumber of spice-processing factories in this coun-try. This study was carried out to investigate theeffect of exposure to respirable spice dust (PM10)to the lung function and respiratory symptoms

of workers employed in three spice factories inSelangor.

MATERIALS AND METHODSThis study involved a total of 117 participantsand the usage of health questionnaires (forrespiratory symptoms survey), a spirometer (lungfunction test) and a diaphragm pump (dustmeasurement). All instruments were calibratedprior to every session of test in every studylocation.

Subjects and LocationsThree similar spice factories located in Selayang,Puchong and Rawang were randomly selected asthe study locations to represent spice factoriesin Selangor and Universiti Putra Malaysia (UPM)for the control.

Since smoking and asthma are known to beamong the dominant confounders in spirometrystudies, only those who were non-smokers andnon-asthmatics were randomly selected to per-form the spirometry test. The selected 56 work-ers (39 males, 17 females) from the 3 factorieswere constandy exposed to mixed spice dustincluding coriander, turmeric, chili, pepper, car-damom and cloves during the work-shifts. Al-most all subjects did not wear masks to protectagainst dust inhalation. Such exposure was notexperienced by the 61 controls (36 males, 25females).

All parameters known to be majorconfounders in spirometry studies (sex, age,height, race) were taken into account in theanalysis (Table 1).

TABLE 1Comparison of lung function measurements between study groups

Age (years)Height (cm)Weight (kg)VC (L)FVC (L)FEV, (L)FEV/FVC%FEFrS2jr 25-75%FMFT (s)

Male (mean ± SD)

Controls(36)

35.24163.4965.783.083.142.26

78.371.930.99

± 62.46± 34.80± 72.36± 3.24± 4.02± 3.24± 3.05± 4.20± 3.36

Workers(39)

37.05164.8367.782.652.391.81

71.362.080.86

± 59.27± 34.53± 55.08± 3.62± 3.56± 3.18± 4.86± 7.37± 3.56

P value

0.39340.26930.34310.0005*0.0000*0.0001*0.0311*0.48640.2564

Female (mean ± SD)

Controls(25)

29.96158.8854.00

2.42.461.89

71.221.900.84

± 38.40± 25.65± 51.15± 1.45± 2.05± 1.95± 3.42± 2.90± 1.65

Workers(l7)

28.80156.2553.78

1.751.591.24

68.741.380.70

± 33.43± 17.77± 20.16± 2.39± 2.89± 2.72± 16.41± 3.05± 0.91

P value

0.59410.0479*0.90760.0000*0.0000*0.0001*0.84720.0065*0.0886

*signiflcant difference (t-test, p<0.05)

62 PERTANIKA J. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000

EFFECTS OF SPICE DUST ON LUNG FUNCTIONS AND RESPIRATORY SYMPTOMS IN WORKERS

Dust Measurement

Physiologically, only particles less than lOum or(forced expiratory volume in 1 second) wasdetermined, and other parameters including

PM]0 (also termed as respirable dust) is known FEFW75% (mid-expiratory flow volume) and FMFTto be inhaled into the inner respiratory system,affecting the ventilatory lung function and alsoresponsible for the prevalence of respiratorysymptoms (Brewis 1985). Therefore, only PMH)

was measured instead of total dust in the work-ing areas. The PM10 concentration was deter-mined using a diaphragm pump (Kimoto MP-1)that trapped particles less than 10\im on a 37mmdiameter, 0.8[A pore size cellulose acetate filterpaper. The PM)0 concentration in ^ig/m3 wascalculated using the formula below:-

PM1

W(g) x 109

F(L/min) x 10"* x T(min)

W = weight of particles trapped on filterpaper in gram

F x flow rate of air drawn into thesampling device (2L/min)

T = duration of sampling

The aerial sampling in both UPM and the facto-ries was done continuously from 9.00 am-5.00pm (working hours). The machine was placedas close to the workers as possible without dis-turbing them.

Lung Function Tests

Lung function tests were performed by the sub-jects during working hours using a spirometer(Vitalograph, England; ATS standards) withstandard techniques (American Thoracic Soci-ety 1979). Each subject performed at least threeattempts of VC (vital capacity) and FVC (forcedvital capacity) with a gap of at least a minutebetween attempts. From the best curve,

(forced mid-expiratory flow time) were calcu-lated. The measurements were then convertedinto BTPS unit. Height was also measured.

Respiratory Symptoms

Structured questionnaires based on the Ameri-can Thoracic Society (1979) were distributed toeach subject prior to lung function test. All ofthe participants were required to answer thequestions in detail with regard to their personaland medical background, respiratory symptomsand history, smoking habit and occupationalhistory.

RESULTS

Dust Measurement

Fig. 1 shows the values of PM10 concentrationmeasured in UPM and the spice factories. InUPM, the dust concentration was only 101 ng/m\ The mean concentration in the factorieswas 2496^ig/m3, which was more than 20-foldhigher than the control area. However, thelevel is far below the OSHA standards of 5000for respirable dust for 8-hour exposure for work-ers. The high concentration measured in Fac-tory 3 might be due to the non-stop workinghours (2 shifts) and the fact that it was thelargest operating spice factory compared to theother two. Despite the high concentration, themajority of the workers did not wear any mask.

Subjects

The subjects and controls were 16 to 59 years ofage. Table 1 shows the physical background ofthe respondents. There is no significant differ-ence in the physical parameters among the male

3500

3000-K

UPM(ctrf)

Fig, L Mean PM10 concentration in the control and study areas

PERTANIKA J. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000

HAMDAN NOOR, WAHIDAH SANSI, ZOLKEPLI OTHMAN and FARIDAH MOHAMAD

subjects, while for the females, a significant dif-ference was observed in height (t-test, p<0.05).

Lung Function Tests

Table 1 also shows the spirometry values of thesubjects. The workers performed significantlylower VC, FVC and FEV1 compared to controls(t-test, p<0.05) for both the male and femalegroups respectively. The male workers alsoexhibited lower FEV1/FVC% compared to con-trols, suggesting a possible obstructive problemin their lungs. Since other confounders such asage and height between the male workers andcontrols did not show any significant difference,a reduction in their lung functions could possi-bly be associated with exposure to spice dust. Inthe female groups, the reductions in lung func-tions of the workers were expected due to thesignificantly lower values of height compared tocontrols. However, the reductions might also beattributed to the additive effect of exposure tohigh concentration of spice dust during workinghours.

Table 2 shows the spirometry values of themale workers according to period of employ-ment. The male workers (no difference inother physical characteristics) who had workedmore than 5 years showed significandy lowermean values of VC and FVC compared to thosewith less duration of service. These statisticalresults suggest that lung function might worsenif the workers are constantly exposed to spicedust over a long period of time.

Respiratory Symptoms

Table 3 compares the prevalence of chronicrespiratory symptoms in the workers and controlsubjects. The most frequently reported symp-toms* was morning coughs, experienced by morethan 80% male workers compared to none forthe controls; followed by chest tightness, experi-enced by most of the workers especially duringwork-shifts. The female workers showed a higherpercentage of respiratory symptoms comparedto controls and the male groups.

TABLE 2Spirometry values of male spice workers according to period of employment in the spice factories

Number of subjectsAge (years)Height (cm)Weight (kg)VC (L)FVC (L)FEVl (L)FEF25-75%FMFT (s)

*significant difference

Symptoms

1. Morning cough4-5 times a week

2. Phlegm4-5 times a week

3. Chest tightnessDuring sicknessDuring workshift

Less than !

15

3 years

33.12 ±11.58164.89 ±64.85 ±

2.85 ±2.58 ±1.85 ±1.95 ±0.94 ±

(t-test, p<0.05)

Percentage

Controls

_

-

2.5-

2.52.5-

5.699.390.440.320.350.700.59

Period of employment

More than 5 years

TABLE 3of respiratory

MaleWorkers

86.329.4

49.09.8

84.362.776.5

2437.48 ± 8.71

162.04 ± 5.6666.76 ±14.452.44 ± 0.642.22 ± 0.721.77 ± 0.402.21 ± 1.540.78 ± 0.54

symptoms

FemaleControls

_

-

4.0-

4.04.0-

P-value

0.13590.07980.57610.0105*0.0250*0.56940.43590.3191

Workers

96.425.0

50.010.7

96.457.175

64 PERTANIKA ]. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000

EFFECTS OF SPICE DUST ON LUNG FUNCTIONS AND RESPIRATORY SYMPTOMS IN WORKERS

DISCUSSIONOur study suggests that constant exposure tohigh levels of spice dust in spice factories (evenbelow the OSHA standards) might have possibleadverse effects on the lung functions of theworkers. Studies done on Yugoslavian spiceworkers showed similar findings even thoughthe workers were exposed to a much lower dustconcentration (Zuskin et aL 1988).

Despite the homogeneity in age, height andweight (determinants of lung capacity) betweenthe participants, the workers showed significandylower values of VC, FVC and FEVj compared tocontrols. Therefore, the reduction might beattributed to the difference in exposure levelbetween the study groups.

The effect of spice dust on the workers wasfurther evidenced by the significantly lowerspirometry values shown by workers who haveworked for more than 5 years, despite the insig-nificant difference in other confounders com-pared to those with less period of service. Thisobservation strengthens our hypothesis that re-duction in lung function is strongly associatedwith the constant exposure to spice dust over along period of time.

Besides this chronic decrease in lung func-tion, Zuskin et aL (1988) also reported acutereductions in lung functions after a work-shift inspice factory workers. Other researchers hadalso observed similar trend in workers exposedto tea and coffee dust (Jayawardana andUdupihille 1997; Zuskin et al. 1979; Zuskin andSkuric 1984).

As expected, higher prevalence of respira-tory symptoms was reported by the workers.This phenomenon is in perfect agreement withother studies elsewhere, some of which hadreported a higher incidence of respiratory symp-toms even without significant reduction in pul-monary function (Blanc et aL 1991).

So far, this study on the effect of spice dustin Selangor is the first that had been reported inMalaysia. Therefore, comparison with data of amatched population from other parts of thecountry is not possible. No further study has yetbeen carried out to determine the chemicalproperties of the spice aerosols inhaled by theseworkers and the mechanisms of toxicity of theaerosol on their respiratory system.

However, we strongly believe that the mecha-nisms proposed by Zuskin et aL (1988) could

play an important role in reducing lung func-tion and increasing the prevalence of respira-tory symptoms in the spice workers. The mecha-nisms include hyperreactivity due to increasedpermeability of the airway mucosa to irritants,resulting in the direct effect on the airway mus-cle damage to the airway mucosa, as representedby the presence of cough in most of the workers(Nadel et aL 1954; Boushey et aL 1980;) repeateddamage of the airway epithelium (Widdicombe1954); and development of inflammation in theairways causing airway responsiveness (Cooper etaL 1986).

Zuskin et aL (1988) also suggested that theadverse effects of spice dust might be due to therelease of mediators in the airway that mightconstrict airway smooth muscle directly or byreflex. Using disodium cromoglycate (DSC),they reported that spice dust affects airway cellscausing the release of these mediators and there-fore concluded that food spice has a bronchoc-onstrictor potential, resulting in reduced lungfunction and increased prevalence in respiratorysymptoms, as observed in this study.

CONCLUSIONObservation from this study suggests that expo-sure to high PM10 of spice dust in spice-produc-ing factories in Selangor leads to increased preva-lence of respiratory symptoms in the workers.The decrease in lung function among the work-ers also suggests that they might be facing otheracute and chronic lung diseases. In addition,the high concentration of dust measured in thefactories suggests that there is a need to improvethe ventilation in these factories, and introducepersonal protective equipment such as mask, inorder to safeguard the respiratory system ofworkers.

REFERENCESAMERICAN THORACIC SOCIETY. 1979. ATS statement-

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BLANC, P., D. Liu, C. JUAREZ and H.A. BOUSHEY.

1991. Cough in hot pepper workers. Chest99: 27-32.

BOUSHEY H.A., MJ. HOLTZMAN, J.R. SHELLER and

J.A. NADEL. 1980. Bronchial hyper-reactivity.Am. Rev. Respir. Dis. 121: 389-413.

PERTANIKA J. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000 65

HAMDAN NOOR, WAHIDAH SANSI, ZOLKEPU OTHMAN and FARIDAH MOHAMAD

BREWIS, R.A. 1985. Lecture Notes on Respiratory

Disease, 4th ed. Singapore: Blackwell Scien-tific Publications.

BROOKS, S.M. 1985. Occupational asthma. In:Bronchial Asthma, eds. E.B. Weiss, M.S. Segal,M. Stein. 2nd edn., p. 461-493. Little Brownand Co.

CHAN O.Y., C.S. LEE, K.T. TAN and T.

THIRUMOORTHY. 1990, Health problemsamong spice grinders. / Soc. Occup. Med.40: 111-5.

COOPER J.A.D. Jr., M.G. BUCK and J.B.L. GEE.1986. Vegetable dust and airway disease:Inflammatory mechanisms. Environ. HealthPerspecL 66: 7-15.

FELLERONI A., C.R. ZEISS and B.S. LEVITZ. 1981.

Occupational asthma secondary to inhala-tion of garlic dust. J. Allergy Clin. Immunol.68: 156-60.

FULLER R.W., CMS. DIXON and P.J. BARNES. 1985.

Bronchoconstrictor response to inhaled cap-saicin in humans. / Appl PhysioL 58: 1080-84.

GOHTE C.J., G. WEISLANDER, K. ANCKER and M.

FORSBECK. 1983. Buckwheat allergy: healthfood and inhalation health risk. Allergy 38:155-59.

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Ventilatory function of factory workersexposed to tea dust. Occup. Med. (Oxf) 47:105-9.

NADEL J.A., H. SALEM, B. TAMPLIN and Y. TOKIWA.

1954. Mechanisms of bronchoconstrictionduring inhalation of sulfur dioxide. / . Appl.PhysioL 20: 164-67.

SUHONEN, R., H. KESKINEN, F. BJORKSTEN, E. VAHERI

and A. Zitting. 1979. Allergy to coriander: Acase report. Allergy 34: 327-30.

TOORENENBERGEN A.W. and P.H. DIEGES. 1985. IgE

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URAGODA C.G. 1966. Symptoms among chilligrinders. Br. J. Ind. Med. 24: 162-64.

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WIDDIECOMBE, J.G. 1954. Receptors in thetrachea and bronchi of the cat. / . PhysioL(London) 123: 71-104.

ZUSKIN E. and Z. SKURIC. 1984. Respiratory func-tion in tea workers. Br. J. Ind. Med. 41: 88-93.

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tory function in coffee workers. Br. J. Ind.Med. 36: 117-22.

ZUSKIN, E., Z. SKURIC, B. KANCELJAK, D. POKRAJAC,

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Received: 30 April 1999Accepted: 30 May 2000



Leaf Growth and Stomatal Sensitivity after Water Stress Reliefand its Relation to Xylem Sap Absicisic Acid

MOHD RAZI ISMAIL1 and WJ DAVIES2

department of Agronomy and Horticulture,Universiti Putra Malaysia. 43400 UPM, Serdang, Selangor, Malaysia

department of Biobgical Science, University of Lancaster,Lancaster LAI 4YQ United Kingdom

Keywords: pepper (Capsium annuum); after effect: water stress: water relations: stomatalconductance: absicisic acid

ABSTRAK

Pengaruh tanaman dli (Capsicum annuum L. var Bell Boy) yang di beri pemulihan tegasan air yang diberikan secara perlahan telah di kajL Pokok di beri tegasan air selama 5 dan 10 hari kemudian di beripengairan semula. Pertumbuhan daun, katian air, konduksi stomata dan kandungan asid absisik (ABA) didalam xilem di bandingkan di antara pokok yang didedahkan kepada tegasan air dan tanpa tegasan air.Potensi air daun telah pulih dengan cepat apabila pokok yang didedahkan kepada tegasan air di beri pengairansemula tetapi konduksi stomata tidak pulih sehingga 48 jam selepas di beri pengairan. Kepekatan ABA di dalamxilem menyamai kepekatan ABA pada pokok yang disiram air berterusan selepas 6 jam di beri pengairan. Selepasdiberi pengairan, pertumbuhan pokok diberi rawatan tegasan air selama 11 hari adalah cepat dan melebihipertumbuhan pokok yang didedahkan kepada pengairan berterusan. Pokok yang berada pada tegasan airberterusan menunjukkan pengurangan pertumbuhan daun, konduksi stomata dan pertambahan kepekatan ABAdidalam xilem.

ABSTRACT

Responses of pepper seedlings to rewatering after being subjected to 5 and 11 days of gradual water stress wereinvestigated. Leaf growth, water relations, stomata conductance and xylem sap ABA in these plants werecompared with plants grown under continuous well watered and stressed conditions. Leaf water potentialreturned to the control values immediately after rewatering but the stomatal conductance of stressed plants did notrecover until 48h after rewatering. The concentration of ABA in the xylem sap in the pre-treated stress plantsreturned to similar values to the control 6h after rewatering. After rewatering, leaf growth of plants pre-treatedwith lid of water stress was rapid and exceeded growth of continuously well watered plants. The plants grownunder continuous water deficit show reductions in leaf growth, stomata conductance and increase in xylem sapABA.

INTRODUCTION

When plants were exposed to drought, theirgrowth rate is impaired due to severalphysiological and biochemical processes beingdisturbed. Over the past decade, the role ofABA induced leaf growth and stomatal closurehas been investigated and reviewed extensively(Passioura et al 1993; Schulze 1994). Researcheshave been concentrated on the responses ofduration of water deficit on leaf growth and

stomatal closure in relation to ABA, but litdeinformation is available on the ability of plantsto recover upon stress relief. Under fieldconditions in the tropics, plants were normallysubjected to a period of gradual water stress andon several occasions, this period of water stressis followed by period of rainfall. Gates (1955)indicated that plants which were exposed to abrief period of water stress and then rewatered,showed a better stomatal regulation, and hence

MOHD RAZI ISMAIL, and W. J. DAVIES

productivity. This supported the earlier findingsby Moroton and Watson (1948) who foundrenewed growth and development uponrewatering in sugar beet, which often proceededat a more rapid rate than in the continuouslywatered plants. There were reports on thestomata responses that upon rewatering areassociated with ABA metabolism. Doerffling etal (1977) reported that a delayed recovery instomatal was due to elevated ABA persistingseveral days after relief of stress. Similarly,Correria and Pereira (1994) showed a 100-foldincrease in apoplastic ABA concentration withsoil drying but did not return to pre-stress valuesimmediately following rewatering. In contrast,several other investigators reported that the delayin stomatal recovery is not associated with theresidual ABA following rewatering (Loveys andKreidemann, 1973; Cornish and Zeevart, 1985).The discrepancy could be contributed to theexperimental procedures, genotypic differencesor plants parts in which ABA have been detected.In pepper plants, Aloni et al. (1991) indicatedthat leaf water potential returned to the controlvalues 24 h after rewatering but photosyntheticrate of stressed plants did not recover and wasdependent on the extent to which the waterpotential had decreased during stress. To ourknowledge, the roles of ABA influencing leafgrowth and stomata closure upon stress relief inpepper plants has not yet been investigated. Inthis paper, we report the plant responses uponstress relief and examine the role of ABAinfluencing leaf growth and stomatal response.

MATERIAL AND METHODS

Experimental Procedures

Seed of pepper {Capsicum annuum cv Bell Boy)were germinated in seed trays under greenhouseconditions. After 7 d, seedlings were transferredto pots with a diameter of 90mm containing amixture of John Innes compost No 2 and grit.At the 5-6 leaf stage seedlings were transferredto the polyvinyl-chloride (PVC) tubes which werefilled with a similar compost mixture. The PVCtubes of 105mm inside diameter and 300mmlength accommodated 3.2 litres of compostmixture. The plants in the column were grownin the controlled environment cabinet withtemperature at 22-25° C (day) or 18° C (night),relative humidity of 48%-56% and photoperiodof 14h with PFD average of 320 umol nr2 s1.The plants grown with daily watering in the

growth cabinet for acclimation. The plants weredivided into four groups in which two groupswere watered daily or left unwatered. The othertwo groups consisted of plants that were leftunwatered for 5 and 11 days, and then rewatered.The plants randomly arranged in the growthcabinet in four replicates. Leaves were taggedprior to treatments for determination of leaflength increment. Water relations, stomatalconductance and leaf growth were measured at3, 6, 24, 48, 72, and 96 h after rewatering. Thepre-stress values were also recorded priorrewatering. Xylem sap was collected from eachplant by extracting extrudate from cut stemprotions. A pressure of 0.3 — 0.5 Mpa above thebalance pressure was applied for the collectionof extrudate. The first 5mm of extrudate wereexcluded from the samples. The measurementsof leaf water potential and stomatal conductancewere carried out on the same leaf. Xylem sapABA was determined from the extrudate fromthe cut stem portion of the same plant.

The mean volumetric soil water content wasmeasured in the soil column prior to wateringthe plants. Three random samples were takenfor each treatment and after oven<lrying at 80°Cfor 48h, soil water content was calculated. Leafwater potential was measured on the youngestfully expanded leaf using a pressure chamber oneach sampling day. These leaves were theninserted into the 10ml syringe and immediatelyplaced in liquid nitrogen before storage in adeep freezer at -20°C for 5 d before determinationof osmotic potential. Two fractions of leafextrudates were collected from each leaf andosmotic potential of extrudates was determinedusing a vapor pressure osmometer. Turgorpotential was calculated from the differencebetween water potential and solute potential.

Measurements of stomatal conductance weremade on the abaxial surface of the youngestfully expanded leaves with a diffusion porometer(AP-4, Delta-T Devices Ltd, Cambridge).

Leaf length and breadth increments weredetermined on the leaves that were tagged beforetreatments began. The leaf length and breadthincrements were calculated at each samplingdate by measuring the differences between thelength on the sampling date and the initialmeasurement.

Concentration of xylem sap ABA wasdetermined using a radioimmuoassay (RIA)(Quarrie et at 1988).

68 PERTANIKAJ. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000

LEAF GROWTH AND ABA TO WATER STRESS RELIEF

RESULTSMean moisture content from different portionof soil column supporting plants was 0.34gcm"3, 0.25 g cnr3 and 0.18g cm"8 under wellwatered, 5 and 11 d of water stress, respectively.This reduction in soil moisture content hadreduced leaf length by 2 and 4.4 cm in plantswhich were subjected to 5 and 11 of water stress,respectively, compared to the well wateredconditions (Fig. 1). Restoration of water to theplants that were pre-stressed resulted in aresumption of leaf growth. The recovery seemeddependent on the duration of plants being leftunwatered. These was an over recovery in leafgrowth on the plants that were subjected to 11 don water stress 24 h after rewatering (Fig. 2).

Leaf length (cm)

12 :

Leaf breadth (cm)

12

10

8

6

4 -

2

0

I i0 5 11 0 5 11

Days of water stress

- 10

8

6

- 4

2

- 0

Fig. 1. Leaf length and breadth of pepper plantsexposed to duration of water stress. Bars represent S.E.

Each point represent means of replicates.

Fig. 3 shows the change in water relations aswater was restored to the soil column of waterstressed plants. Leaf water potential had alreadydeclined to -0.65 Mpa and -1.09 M(3a whenplants were left unwatered for 5 and 11,respectively. Upon restoration of water, leafwater potential in plants that were subjected topre-stress treatments, increase immediately andmaintained at a similar value to the controlthroughout the experimental period. Osmoticpotential of plants subjected to water stress forl i d , maintained a lower osmotic potential butincreased progressively after rewatering. Asexpected, plants that were subjected tocontinuous water stress maintained a continuous

Days of water stressFig. 2. Cumulative leaf and breadth of pepper plantsafter rewatering. • = well watered, • = water stress

for 5 days and rewatered: \ | = water stress for 11 daysand rewatered: O = continuous water stress. Bars

represent S.E. of 6 replicates.

lower osmotic potential. These changes in leafwater potential and osmotic potential in plantssubjected to various treatments resulted inchanges in turgor potential in which plants leftunwatered for l i d and rewatered, maintainedhigher turgor than the other treatments.

Stomatal conductance declined progressivelywith the cessation of watering to the plants,reaching to less than lOOmmOl m~2s~l after 4 - 5d of water stress. Once plants were rewatered,stomatal conductance began to recover, but notuntil 48h to reach a similar values to the control.Similar to the effects on leaf length increment,



--•••y- - f " |

0 20 40 60 80 100 120

Time (h)

Fig. 3. Changes in water relations upon stress relief ofpepper plants. # = well watered, • - rervatered after 5

days of water stress; \"} = rewatered after 11 days ofwater stress; O • continuous water stress. Bars

represent ± SE of 4 replicates.

there were was a tendency that the plants stressedfor 11 d to recover at a greater rate than controlplants 96h after rewatering (Fig. 4).

Xylem sap ABA in pepper plants whensubjected to water stress for 5 and l i d , increasedfrom less than 40umol m"3 to over 160umoln r \ Xylem sap ABA decreased rapidly in theseplants after restoration of water to a similarvalues to the control 6h after rewatering.Xylem sap ABA in continuous water stress plantsincreased as water stress proceeded. (Fig. 5).

600

500 H

E 400

!

300o

3

< 200Q.CO

100

X

... /

IM—•-L>S0H"P':"'"

f '• 1 [ I T • 1

-20 0 20 40 60 80 100 120

Time(hr)

Fig. 5. Xylem sap ABA of pepper plants. • * wellwatered : • = rewatered after 5 days of water stress :

G = rewatered after 11 days of water stress :O = continuous water stress. Bars represent

± SE of 4 replicates.

, ^800

I 600

§400

S0 200

\

0 2 4 6 S 10 12

cl3ys from withotomg w3ter

1 0 2 C 3 0 4 0 SO 60 70 B0 90100

hours after rewatenng

Fig. 4. Stomatal conductance of pepper plants exposed to duration of water stress and the effect on rewatering (well watered : M reivatered after 5 days of water stress: (Q) rewatered after 11 days of water stress;

(D) continuously stress. Bars represent S. E. Each point represent means of 6 replicates. Measurements afterrewatering at 6 hours were carried out at 6pm where plants had already being exposed to 12 hours

of light period and relative humidity had declined to 39% RH.


LEAF GROWTH AND ABA TO WATER STRESS REUEF

DISCUSSIONThe reduction in leaf growth is considered asthe most sensitive response to water stress inmost plant species (Hsiao, 1973; Dale, 1988).The causes of this reduction could be eitherhydraulic or non hydraulic. Under progressivedevelopment of water deficit, the reduction inleaf growth has been correlated with high levelsof ABA in leaves or xylem sap (Zhang andDavies, 1990; Passioura, 1988). In our earlierinvestigation, we showed that early reduction inleaf growth of pepper species occurred withoutany detectable changes in leaf water potentialbut coincided with a slight increase in xylem sapABA (Mohd Razi and Davies 1997). In thisexperiment, we show a recovery of leaf growthand stomata conductance upon stress relief. Therecovery was greater than the control plantsespecially when plants were rewatered after l i dof water stress. Plants that were pre-stressed fora period of 5 d and then rewatered resumegrowth at a similar rate as the control. Theresumption of leaf growth and stomatalconductance at a similar of greater rate than thecontinuous well watered plants upon stress reliefis consistent with those observed in earlier studyon several plant species (Morton and Watson1948; Kramer 1950; Gates 1955). Kleinedorst(1975) indicated that an inhibition in leaf growthin maize plants to be due to retardation in cellelongation rather than in cell division, andtemporary accelerated leaf growth occurred ondiscontinuing the stress condition. This supportsearlier suggestions by Hsiao and Acevedo (1974)who indicated that the reduction in growthduring a mild and short water stress could beoffset completely by a rapid transitory phase ofgrowth following release of stress. Aloni, Daieand Karni (1991) investigated the recovery ofyoung transplant pepper plants grown in a rapidsoil drying, however, showed a contradictoryresults on the leaf growth response upon stressrelief. They reported that plants which werestressed for 24 and 48h and then rewatered,resume leaf elongation but did not attain similarvalues as the control even after 10 d and ofrewatering due to the disturbance of assimilatepartitioning.

The stomatal conductance did not attain asimilar values to the well watered plants until48h after rewatering. This is consistent withobservation byCorreiaand Perreira (1994) uponrewatering of lupins plants exposed to 5 d of

stress, but their data did not show a completerecovery as their experiment was terminatedbefore 48h after rewatering. As watering proceedto the pre-stress plants, stomatal conductanceattained a similar of greater value to the controlsimilar to those observed on leaf growth. Thedays to a complete recovery of stomatalconductance on plants that were previouslystressed and rewatered varied according tospecies e.g: 205 d for tobacco; Fischer, Hsiaoand Hagan (1970); 14 d for conifer (Jackson elal 1995).

When plants were rewatered after a periodof water stress, stomatal conductance recoversmore slowly than leaf water status. Correia andPereira (1994) indicated that extent of recoveryof stomatal conductance upon stress relief isassociated with the changes in concentration ofABA in leaf apoplast. They, however, were notable to show a consistent response in a laterreport (Correia and Pereira 1995). Our resultssuggest that one of the possibilities in an earlyrecovery of leaf growth and stomatal conductanceduring stress relief is due to immediate declinein xylem sap ABA. As watering progressed, thisrole of ABA diminished particularly in plantswhich were subjected to 11 d of water stressbefore rewatering. In this case, we could suggestthat the recovery of leaf growth due to higherosmoregulation in plants previously subjected towater stress and then rewatered. Fisher et al(1970) suggested that the stomatal openingpotential of a given leaf is related to ageingduring which there was as increase in the numberof leaves separating the leaf from the apex.Since post-stress leaves were closer to the apexrepresenting a physiological younger statecontribute to the better stomatal openingcompared to the control. Cornish and Zeevart(1985) rewatered the wilted Xanthium plantsand found that the stomatal reopening did notcoincide with the decline of bulk leaf ABA butas a result of elevated levels of ABA remained inthe apoplast after the bulk leaf contents hadreturned to their pre-stress values. We, however,would not be able to suggest the role of ABA inrewatered plants since stomatal conductance wasat least 60% lower than the continuous wellwatered plant 24 h after rewatering when ABAhas already declined to a similar values to thecontrol. We could argue that with a gradualdevelopment of soil water deficit, it is possiblethat when plants were watered, ABA could be

PERTANIKAJ. TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000 71


more diluted and the concentration would besimilar to the well watered plants. There aremany reports suggesting that under condition ofslight decline in soil moisture content, stomatalclosure precedes any detectable increase in xylemsap ABA (Trejo and Davies, 1991; Jackson et al1995). It has been suggested ABA does notimpinge direcdy on stomata immediately afterroots were subjected to soil drying. This hasbeen suggested earlier b Weyers and Hillman(1979) indicating that although stomatalreopening occurred when net efflux of ABA wasallowed, it is not possible to suggest that uptakeof ABA as a single factor was directly related tothe events of stomatal closure. The eventsleading to abscicic acid-evoked stomata closurehas been discussed by Blatt and Thiel (1993)who indicated that the progression of eventsfrom ABA stimulus is not linear and least passthrough Ca and pH intermediate.

Our attempt to explain the recovery ofstomata conductance and leaf the basis of thedecline in ABA after restoration of water todrying soil, was inconclusive. Relief from waterstress results in a decline in ABA concentrationto a pre-stress values within a few hours. Thestomata, however, require at least 48h to achievevalues similar as the continuous well wateredplants. We speculated that there may be alsoinvolvement of hydraulic factors which regulatecell metabolism in the process of recovery towater stress. The over recovery of leaf growthand stomata response upon restoration of waterto the drying soil presumably is associated withthe physiological *y°unger> condition followingturgor recovery.

ACKNOWLEDGEMENTMohd Razi Ismail would like to thank BritishCouncil for the British High CommissionerResearch Award and Universiti Putra Malaysiafor granting sabbatical leave. We thank JaneMartin for her assistance in ABAradioimmuonoassay.

REFERENCESALONI, B. J. DAIE and L. KARNI. 1991. Water

relations, photosynthesis and assimilate par-titioning in leaves of pepper {Capsicumannuum) transplants: Effect of water stressafter transplanting, / Hart. Sci 66: 75-80

BLATT, MR and G. THIEL. 1993. Hormonal con-trol of ion channel gating Ann. Rev. PlantPhysioL and Plant Mol. Biol. 44: 543-567

CORNISH, K and J.A.D. ZEEVART. 1985. Abscisicacid accumulation by roots of Xanthiumstrumarium L. and Lycrpersicon esculent Millin relation to water stress. Plant PhysioL 79:653-8

CORREIA, MJ and SJ PEREIRA . 1994. Abscicicacid in apoplastic sap can account for therestriction in leaf conductance of white lu-pins during moderate soil drying and afterdewatering. Plant, Cell and Environ. 17: 845-52

CORREIA, MJ. and J.S. PEREIRA. 1995. The controlof leaf conductance of white lupin by xylemABA concentration decreases with the sever-ity of water deficits,/ Exp. Bot, 46: 101-10

DOERFFLING, K, STRECTH, J. KRUSE W and B.

MUXFELDT. 1977. Absciccis acid and theafter effect of water stress on stomatal open-ing potential. Zeitschrift fur Pflanszenphysiol.81: 43-56

FISHER, R.A, T.C. HSIAO and R.M. HAGAN 1970.

After-effect of water stress on stomatal open-ing potential . I. Techniques and magni-tude. / Exp BoL 21 371-85

GATES, C.T. 1955. The response of young to-mato plants to a brief period of water short-age I. The individual leaves. Aust. J. Biol.Sci. 8: 215-230

HSIAO, T.C 1973. Plant responses to water stress.Ann Rev. Plant PhysioL 24: 519-70

HSIAO, T.C. and E. ACEVEDO. 1974. Plant re-sponses to water deficits, water use efficiencyand drought resistance. Agric. Meteorology 14:59-84

JACKSON, GE., IRVINE, GRACE, J., A.A.M KHALIL.

1995. Abscicic acid concentrations a n dfluxes in droughted conifer saplings. PlantCellEnvrion. 18: 13-22

KLEINENDORST, A. 1975. An explosion of leafgrowth after stress conditions. Neth. J. Agric.Sci. 20: 203-217

KRAMER, PJ. 1950. Effect of wilting and thesubsequent intake of water by plants. Amer.J. Bot. 37: 280-284


LEAF GROWTH AND ABA TO WATER STRESS RELIEF

LOVEYS, B.R. and P.E. KRIEDEMANN. 1973. Rapidchanges in absecissic acid-like inhibitors fol-lowing alterations in vine leaf water poten-tial. PhysioL Plant 28: 476-79.

MORTON, A.G. and DJ WATSON. 1948. A physi-ological study of leaf growth. Ann. Bot 12:281-310.

PASSIOURA, J.B. 1988. Root signals control leafexpansion in wheat seedlings growing indrying soil. Aust. J. Plant PhysioL 15: 687-93

PASSIOURA, J.B., A.G. CONDON and R.A. RICHARDS.

1993 Water deficits, the development of leafarea arid crop productivity. In Water Deficits,Plant Responses from Cell to Community, ed.J.A.C Smith and H. Griffiths, p. 253-264.Oxford, UK : Biois Scientific Publisher.

QUARRIE, S.A. WHITFORD, P.N. APPLEFORD N.E.J.WANG, T.L, COOK S.K., HENSON, I.E and B.R.

LOVE\S. 1988 A monoclonal antibody to(S)-abscicic acid: its characterization anduse in a radiommunassay for measuringabsicic acid in crude extracts of c e r e a land lupin leaves. Planta 173: 330-9

SCHULZE, E-D, 1994. The regulation of planttranspiration: Interaction of feed forward,feedback, and futile cycles. In: Flux Controlin Biologcal System, ed. E.D. Shulze, p. 203-235. Academic Press.

TREJO, C.L. and WJ DAVOES. 1991. Drought in-duced closure of Phaseolus vulgaris L. sto-mata precedes leaf water deficit and anyincrease in xylem ABA concentration. / .Exp. Bot. 42: 1507-15.

WEYERS, JJD.B and J.R. HILLMAN. 1979 Uptakeand distribution of abscicic acid inCommelina leaf epidermis. Planta 144: 167-172

ZHANG, J. and WJ DAVIES. 1990. Does ABA in thexylem control the rate of leaf growth insoil dried maize and sunflower plants? / .Exp. Bot 41: 1125-32.

(Received: 27 April 1999)(Accepted: 29 December 1999)



CERES-Maize Simulation Model: Establishment of PlantingWindows for Grains Maize under Rainfed Conditions

H. ABD. RAZAK1, B. Y. AMINUDDIN1 and R. MOHD FAUZI2

Strategic, Environmental and Natural Resources Research CentreMalaysian Agricultural Research and Development Institute

Mardi} G.P.O. Box 12301,50774 Kuala Lumpur, Malaysia

2Department of Crop ScienceUniversiti Putra Malaysia

43400 Serdang, Selangor, Malaysia

Keywords: crop model, planting window, ecological zone

ABSTRAK

Konsep jangkamasa pertumbuhan atau peluang menaman merupakan satu pendekatan yang berguna dalammengenalpasti masa menanam yang sesuai terutama di bawah pengurusan tanaman tanpa pengairan. la dapatmembantu petani dalam menentukan kejayaan tanaman yang diusahakan. Model simulasi tanaman (modelCERES-Maize) telah digunakan untuk mengenalpasti masa yang sesuai untuk menanam dan jagung digunakansebagai tanaman penunjuk. Keupayaan model dalam membuat ramalan juga turut ditentukan berdasarkankeputusan-keputusan simulasi yang telah direkodkan. Model menunjukkan berkeupayaannya dalam meramalpengeluaran hasil jagung sebenar di peringkat percubaan tetapi selalu melebihi jangkaan bagi ramalan diperingkat ladang. Dalam persekitaran setempat dengan keadaan tanah dan cuaca yang sesuai, potensi hasiljagung dapat dijangkakan melebihi 7 t/ha. Potensi hasil untuk kebanyakan zon adalah rendah padapenghujung tahun disebabkan keadaan kemarau yang dialami oleh tanaman sepanjang musim. Berdasarkanbentuk potensi hasil, ia selaras dengan bentuk taburan hujan. Dengan gabungan had limit hasil 5 t/ha, iamenunjukkan kebanyakan dari zon-zon tersebut mempunyai dua musim menanam kecuali dua zon (1 dan 26)yang hanya mempunyai satu musim menanam sahaja. Di samping itu masa yang paling sesuai dalam musimmenaman bagi zon 9 dan zon 10 turut juga dikenalpasti Maklumat sebeginilah yang petani-petani perlukandalam membantu mereka merancang aktiviti di ladang ke arah mencapai operasi yang cekap.

ABSTRACT

Grmving period or planting tvindows concepts is a useful approach in identifying suitable planting time for cropunder rainfed management It will help farmers to ensure the crop success. A crop simulation model (CERES-Maize model) was used to identify the suitable planting time and maize was used as an indicator crop. The modelwas validated using compiled data to ensure its fitness within the setup acceptable limit. The model was capableto predict maize yield potential close to the actual yield at the experimental trails but always over estimated at thefarm production levels. Under local conditions with favourable soil and climate, the yield potential of maize couldbe expected greater than 7 t/ha. The yield potentials for most of the zones are relatively low towards the end ofyear due to a dry period, experienced in most of the crop growing cycle. Based on the yield potential trends, itcorresponds to rainfall pattern. In combination with a cut off point at 5 t/ha, its shows most of the zones havedouble planting windows except for two zones (1 and 26), which have a single planting window. In addition,as example the most suitable planting time within the planting window for zone 9 and 10 were also identified.This information can help fanners in planning their farm in order to have the most efficient operation.

INTRODUCTION condition, moisture adequacy is an importantRainfed farming is widely accepted in Malaysia, factor to ensure the successfulness of crop pro-especially by small-scale farmers. Under rainfed duction. A suitable planting time with sufficient

H. ABD. RAZAK, B. Y. AMINUDDIN and M. R. MOHD FAUZI

soil moisture during a planting season should beavailable before planting. Planting window con-cept has been proven to be a very useful ap-proach to ensure sufficient moisture availabilityin the soil. This concept sometimes called thegrowing period was firstly introduced byCocheme and Franquin (1967). The conceptwas defined as the period in a year where agri-culture can be produced due to adequate soilmoisture and absense of temperature limita-tions. The Penman Open-water Evaporation (Eo)method was used in the calculation with precipi-tation as input data.

The concept was then modified by FAO anddefined, as a continuous period in one yearwhere precipitation is greater than half-poten-tial evaporation with a number of days requiredfor evaporation (Kowal, 1978). The Penmansmethod was used in the calculation and with theassumption that soil can only store up to 100mm of rainwater at each precipitation event.

In view of that, an exercise was conductedto identify the planting windows for maize onvarious ecological zones. The CERES-Maizemodel (Kiniry and Jones, 1986) was used in thisstudy instead of Eo and FAO methods. It wasseen to be more reliable whereby actual cropgrowth was taken into account during the simu-lation process. Although only a single crop atone time can be handled by the model, theselected crop can probably show the actual sce-nario of the planting window for some of theother crops. In addition, validity of the modelwas also taken into consideration in this study.

MATERIALS AND METHODS

CERES-Maize Model ValidationBefore embarking the planting window identifi-cations, the CERES-Maize model needs to bevalidated. The validation process is necessarybecause it ensures the model works properlyand the simulation result of the model is withinthe acceptable limit such as Root Means SquareError (RMSE) is less than 1 t/ha or statisticallysignificant at least at 5 % confidence. For thisreason, twenty sets of simulated and measuredgrain maize yield data were compiled. The datawas from experimental trails and farm produc-tions, which were carried out elsewhere. A statis-tical methodology i.e. RMSE was used to analyzethe data, in order to evaluate the fitness of themodel. The RMSE value should be as small aspossible to indicate the best fit between simula-

tion output of the model and actual result fromthe field.

Planting Windows Identification

Simulation ExerciseThe CERES-Maize model was used to simulatepotential yield using the weather, soil and cropdata. Simulations were considered on every tendays, throughout the year of eleven years (1985-1995). Only predicted yield potential at maturitystage of the simulation output was considered.Simulated yield outputs of the same plantingdate from eleven years were singled out usingV80 (80% probability) calculation technique.Finally, each zone has 37 simulated yield datarepresenting a ten-day interval of planting datesthroughout the year.

Two assumptions were made during thesimulation exercises. First, no pest and diseaseinfestations occurred that could cause crop dam-age. Second, free from weed competition foravailable resources such as fertilizer, light, water,etc., which would affect maize crop perform-ance and therefore reduce yield production.

Weather Data Used

Sets of long term weather data, representingeight ecological zones of the northern parts ofPeninsular (Nieuwolt et aL, 1982) were used inthe study. The weather stations where data wereobtained are Kota Bharu representing Zone 26,Kuala Krai for Zone 25, Kuala Terengganu forZone 22, Kuantan for Zone 21, Melaka for Zone12, Petaling Jaya for Zone 10, Sitiawan for Zone9, Chuping for Zone 2 and Alor Star for Zone 1.The data consists of daily solar radiation (MJ/mVday), maximum and minimum temperature(°C) and precipitation (mm/day) from January1985 to December 1995. Each data set wasreformatted as required by the model for simu-lation purposes.

Soil Data Used

A set of soil data, extracted from soil profiledescriptions was used in this study. The soilphysical property inputs were in the form ofthickness of the layer, the lower limit of plant-extractable water, the drained upper limit, watercontent at saturation, a weighting factor forrooting, and initial soil water content as re-quired by the model. The soil chemical proper-ties include organic carbon, pH, initial soil am-monium, and soil nitrate content.

PERTANIKA J. TROR AGRIC. SCI. VOL. 23 NO. 2, 2000

CERES-MAIZE SIMULATION MODEL FOR GRAINS MAIZE UNDER RAINFED CONDITIONS

Crop and Management Data Used.In this exercise, maize cultivar Suwan 1 (Zeamays L var. Suwan 1) that was used by mostfarmers for grain production was selected. Cropmanagement practices were treated as underexperimental condition. The rate of fertilizerused was 120N, 60P O5 and 40K^O kg/ha. Nitro-gen fertilizer was divided into two applicationswhere half of them were applied together withother fertilizers during the planting as a basal.Another half was applied after the crop age of35 days on the field.

Planting Window Identification.The calculated yield data of each zone based onY80 was plotted against planting date. A highyield cut off point i.e. 5.0 t /ha (Abd. Razak),which correspond to actual farm production ofabout 4.0 t/ha, after 10% less due to rats, dis-eases and bores, and 5% less due to mechanicalharvesting loses, was setup. Above the cut offpoint is considered as suitable planting time orwithin a planting window whereby lower is con-sidered outside the planting window.

RESULTSModel Validation

Validity of the CERES-Maize model was evalu-ated based on 20 sets of simulated and meas-ured grain maize yield data. The simulated andmeasured yield under experimental trials rangesfrom 2.7 to 13.6 t /ha and from 2.7 to 14.7 t/ha,respectively. Analysis result shows the differencesbetween simulated and measured yields are rela-tively small where the RMSE is only 586 kg/ha(Table 1) as compared to the acceptable limit,which is 1000 kg/ha.

Under large-scale farm management thesimulated and measured yield on the first sea-son, ranges from 2.3 to 4.7 t /ha and from 5.5 to5.8 t/ha, respectively. In the second season, itranges from 3.5 to 5.5 t/ha and from 5.9 to 6.1t/ha. The RMSE value for the first and thesecond season is 1878 and 1825 kg/ha, respec-tively, higher than the experimental trial (Table2).

TABLE 1Validations of CERES-Maize model under experimental condition

Year

19821989199019911985

1988

1989

Blockname

20 AF20 BD21 AG22 BK23 BE

Location

Urbana Illinois, USAMead NE, USAIbadan, NigeriaIbadan, NigeriaHawaiiHawaiiMARDI Serdang, MalaysiaMARDI Serdang, MalaysiaUPM Serdang, MalaysiaUPM Serdang, Malaysia

RMSEBIAS

Experimental status

High fertilizerHigh fertilizerLow fertilizerLow fertilizerHigh fertilizer,High fertilizer,Low fertilizerLow fertilizerLow fertilizerLow fertilizer

TABLE 2

elevation 77melevation 340m

Validations of CERES-Maize model under large scale farm i

First season 1991

Observed (kg/ha) Simulated (kg/ha)

39704740225046604290

RMSEBIAS

5791567854635686572518781686

Second

Observed(kg/ha)

147001080049044403

11533116002184298438252739

Simulated(kg/ha)

136001070049094760

12339122342717305838703607

586212

nanagement

1 season 1991

Observed (kg/ha) Simulated (kg/ha)

40905010369034905500

6053593660205993600918251646



Estimated Yields on Various LocationsThe results of simulated yield potential in eachecological zone indicate variability at differentplanting time as well as location of the area. Itranges between less than 1 t /ha and more than7 t /ha (Figure 1). In the Northern west andCentral east of Peninsular such as Alor Star,Chuping, and Kuantan, maximum yield at thebest planting time is about 6 t/ha, which isrelatively low compared to the other areas. Thehighest yield, which was above 7 t/ha, is inMelaka and followed by Kuala Terengganu,Sitiawan, Kuala Krai and Kota Bharu at themiddle range. The simulated yields are relativelylow towards the end of the year, except forSitiawan.

Planting Windows on Various ZonesThe model shows the yield potential of grainmaize under local environment is about 7 t/ha.However, annual yield pattern is fluctuated de-pending on the weather condition where pre-cipitation, plays a major role. Figure 1 shows theyield variability in eight climatic zones, repre-senting parts of Peninsular Malaysia. High yieldpotential could be expected when planting dur-ing the wet season while poor yields in the dryseason. Based on the set up yield potential above5 t/ha, planting windows for each location orzone were identified (Table 3). Most zones inthis study have double planting windows exceptZones 1 and 24. Zone 10 has the longestplanting window (10 months) while Zone 24 isthe shortest (5.5 months).

yield (t/ha)

109

- • - A i o r Star—^ Kuaia Terengganu-g—Cuping

BharuKuantanSitiawan

-Kuaia Krai

-Melaka

Planting date

Fig, L Simulated yield potential of grain maize on various climatic zones of Peninsular Malaysia

TABLE 3Planting windows for grain maize in various climatic zones

Ecologicalzone

262422

211210*090102

* Source :

Representative weatherstation

Kota Bharu, KelantanKuala Krai, KelantanKuala Terengganu,TerengganuKuantan, PahangMelakaPetaling Java, SelangorSitiawan, PerakAlor Star, KedahChuping, Perlis

Ismail et al., 1990

Main season

June - OctoberMid May - OctoberMid May - Early October

July - OctoberJune - Early OctoberMid June - DecemberJuly - DecemberFebruary - Mid AugustLate April - Mid September

Off-season

Mid March - Middle April-

March

January - Mid MayLate January - Mid MayJanuary - Mid AprilJanuary - Mid March-

February - March


CERES^MAIZE SIMULATION MODEL FOR GRAINS MAIZE UNDER RAINFED CONDITIONS

DISCUSSION

CERES-Maize Model Performance atExperimental Level

Maize is extremely endurable crop, which canbe cultivated in many conditions and ways. Agro-nomic practice is one of the main factors affect-ing the production level. Favourable climaticand soil conditions with excellent managementpractices will produce higher yields. In the tem-perate region for example, grain yields of morethan 15 t /ha have been reported (Vander Meer1982) while in the lowland tropics, yields mayrange from 5 to 8 t /ha with good management.Adequate nitrogen and potassium with excessphosphorus fertilizer will cause a major increasein maize yield (Miller et al. 1987). In addition,high yielding variety could also play a major rolefor high production. This explains why there isgreat variability of the yields from local andoversea trails (Table 1).

Under such great yield variability, the modelis still capable of predicting reasonable yieldoutput. Statistical analysis shows the overall per-formance of the model for predicting yield po-tential at experimental level is highly significant.It was also confirmed by this study, where theRoot Mean Square Error (RMSE) of simulatedand measured yield was about 586 kg/ha. Asmaller RMSE value (less than 1 t/ha) indicatesthe simulated values are closer to the actualvalues. Kiniry and Jones (1986) found the rela-tionship between simulated and measured yieldswas highly significant (p = 0.0001) and waswithin the 95 % confidence band for the 1:1regression line. Therefore, the model is consid-ered reliable and can confidently be used forsimulating grain maize yield under experimen-tal condition.

Model Performance at Production Farm Level

Under large-scale farm management, the simu-lated yield is always about 10-40 % overestimated(Abd. Razak 1995). The RMSE value at this levelis 1850 kg/ha, which is slightly higher than theRMSE at the experimental level. It is due to theinsufficient soil characteristic data used in simu-lation. The soil data from one point of a bigblock was applied to represent the whole blockof farm production, which is variable and lesshomogeneous. Extra points of detail soil char-acteristic data from a big block are probablyrequired in order to have a better simulationresult. In addition, other two main factors which

probably caused the errors in simulated grainyields are that the soils were not well character-ized and the inaccurate estimates of water statusand the depth of the soil. In this respect, modelshows its stability when dealing with the homo-geneous soil data although under different cli-matic condition. A small difference of RMSEbetween the first and the second season of yieldpotential on the same soil (about 50 kg/ha)from this study confirmed the model stability.The yield potential difference occurs mainly dueto the variability of weather pattern such asprecipitation, radiation and air temperature,between seasons. However, the simulation yieldtrends and the over estimate simulated yieldvalue which were produced by the model arestill within the acceptable limit. Therefore, themodel could be used to simulate the potentialyield under farm production, provided specificmeasures be considered to suit the local condi-tions.

Estimated Yields on Various Zones

The model shows potential grain maize yieldunder local environment is greater than 7 t/ha.However, the yield potential is variable through-out a year depending on the planting date whichinfluence by weather patterns especially annualprecipitation. The amount, distribution and in-tensity of precipitation are very important fac-tors that affect the production of maize espe-cially under rainfed management. Huda et al.(1976) found that the variation in precipitationduring different growth stages had different ef-fects on yield. High yield potential could beexpected when planting in the wet season whilepoor yield potential during the dry seasons.However, excessive precipitation and poor soilcondition will also decrease yield potential (Shaw1977; Young 1980).

Besides precipitation, solar radiation statusis another factor in determining the maximumyield. During simulation, the model assumes 5.0g of dry biomass is produced per MJ of inter-cepted photosynthetically active radiation undernon-stressed condition (Jones et aL 1986). Areaswith high level of radiation during the wet sea-son would produce a higher yield compared tothe zones with cloudy wet seasons. Pendletonand Egli (1969) proved maize yield was higherwith increasing radiation interception. It explainsthe zones such as Kuantan and Petaling Jaya,with much cloudy condition during a rainy sea-



son have low yield potential (about 6 t/ha)compared to other zones.

In addition, the level of crops managementwith phosphorus and potassium fertilizers appli-cation, pest and disease management and weedcontrol, which is not taken into consideration bythe model, is also important contribution to-wards a better crop performance and high yieldproduction.

Planting Windows on Various ZonesIn tropical and subtropical areas, where soilmoisture adequacy is a major constraint to cropproduction, the planting windows or growingperiod concept has proven to be very useful (Syset ai 1991). Inaccurate planting time causescrop failure and very low yield. Generally, to-wards the end of the year, chances to have asuccessful crop are very minimal, except forSitiawan zone because a rainy season of the zonestarted towards end of the year. For other cli-matic zones, such as Kota Bharu, Kuala Krai andKuantan, during the first half of the year areconsidered not suitable for planting due to dryperiod. The planting time of July to mid Sep-tember is considered the best time to have asuccessful crop for all climatic zones.

A combination of total ten days precipita-tion pattern and yield potential, the most suit-able planting time for grain maize within theidentified planting window could be worked out(Abd. Razak 1995). Based on this approach,some zones can have double plantings while theother zones only have a single planting per year.The most suitable planting times for Zone 9 are10 May and 20 September of the year. For Zone10, the most suitable planting times are 14 Feb-ruary and 7 September of the year (Ismail et al.1990).

CONCLUSION

The CERES-Maize model could be used as a toolto estimate yield potential of grain maize through-out the country. A combination of the modeloutput with ten days precipitation pattern couldbe also used to identify the planting windowsand the most suitable planting time for highyield production. With reliable information, itcan help the operator to daily manage the maizefarm efficiendy. High yield production with mini-mal risk of crop failure could be expected.Farmers cum entrepreneurs most likely are moreconfident to invest in the maize cultivation with

such information. Entrepreneurs could also plantheir farms at different locations and plantingtime in the country, targeted for continuousproductions throughout the year with a highreturn.

REFERENCES

ABD. RAZAK, H. 1995, Modelling of the produc-tion potential of commercial grain maize(Zea mays L) using CERES-Model in SitiawanPerak, Malaysia. M. Sc. Thesis, InternationalTraining Centre for Post-graduate Soil Sci-entists. State University Gent, Belgium.

COCHEME, J and P. FRANQUIN. 1967. An

agroclimatological survey of a semi-arid areain Africa, south of the Sahara. World Mete-orological Organization, 86, No. 210, TP110.

HUDA, A. K. S., B. P. GHILDYAL and V. S. TOMAR.

1976. Contribution of climate variables inpredicting maize yield under monsoon con-dition. Agric. MeteoroL 17: 33-47.

ISMAIL A. B., H. ABD. RAZAK, M. M. RADZALI and J.

MOHD. YUNUS. 1990. Use of CERES-Maizesimulation model and rainfall pattern foridentification of suitable planting season forgrain maize. Paper presented at NationalSeminar on Land Evaluation for AgriculturalDevelopment, 20-22 Aug. 1990, Kuala Lumpur.,Org: Mai. Soc. of Soil Science.

RITCHIE J. T.,J. R. KINIRY, C. A.JONES and D. C.

GODWIN. 1986. Model Inputs: In CERES-Maize:A Simulation Model of Maize Grmoth and Devel-opment, ed. C. A. Jones and J. R. Kiniry, p.37-48. College Station, Texas: Texas A&MU. Press.

KINIRY J. R and C. A. JONES. 1986. Model Evalua-tion. In CERES-Maize: A Simulation Model ofMaize Growth and Development, ed. Jones C.A. and J. R. Kiniry, p. 113-144. CollegeStation, Texas: Texas A&M U. Press.

KOWAL, J. 1978. Agro-ecological zoning for theassessment of land potentialities for agricul-ture. In Land Evaluation Standards for RainfedAgriculture, FAO World Soil Resources Re-port 49, FAO, Rome.

MILLER, M. H., W. A. MITCHELL, M. STYPA and D.

A. BARRY. 1987. Effects of nutrient availabil-ity and subsoil bulk density on corn yield


CERES-MAIZE SIMULATION MODEL FOR GRAINS MAIZE UNDER RAINFED CONDITIONS

and nutrient absorption. Can. J. Soil Sc. 52:447-483.

NIEUWOLT, S., M. Z. GHAZALLI and B. GOPINATHAN.

1982. Agro-ecological regions in PeninsularMalaysia. MARDI Special Report.

PENDLETON, J. W and D. B. EGLI. 1969. Potentialyield of corn as affected by planting date.Agronomy Journal 61 : 70-71.

SHAW, R. H. 1977. Climatic Requirement. In Cornand Corn Improvement, ed. G. T. Sprague, p.591-623. Agronomy 18. Madison, WS. USA.

SYS, C., E. VAN RANST, and J. DEBAVEYE. 1991.

Land Evaluation Part I: Principles in LandEvaluation and Crop Production Calcula-tions. International Training Centre for Post-graduate Soil Scientists. State UniversityGent, Belgium.

VANDER MEER, H. G. 1982. Northeast pre<onfer-ence tour, 21. Report of XTV InternationalGrassland Congress. Gebondlder VerslagenNo. 22 NVWV, Wageningen.

YOUNG, A. 1980. Tropical Soil and Soil Survey, p.290-300, 307-311. Cambridge, London: Cam-bridge University Press.

Received: 10 December 1999Accepted: 4 November 2000



Effect of Dactylaria higginsii on Purple Nutsedge (Cyperus rotundus)Interference with Pepper {Capsicum annuum L)

B. KADIR1, R. CHARUDATTAN*, W.M STALL3, and T.A. BEWICK4

1 Department of Plant Protection, Faculty of Agriculture, Universiti Putra Malaysia,43400 UPM Serdang, Selangor, Malaysia

2Department of Plant Pathology,department of Horticulture, University of Florida, Gainesville 32611.

4 University of Massachusetts, Cranberry Experiment Station, East Wareham, MA 02538.

Keywords: Dactylaria higginsii, purple nutsedge, weed interference, bioherbicide, yield loss, crop loss

ABSTRAK

Satu kajian rumah hijau telah dijalankan untuk menilai kesan patogen berkulat, Dactylaria higginsii padanutsedge ungu yang dicampur dengan lada hitam 'Capistrano' (Capsicum annuum) . Tanaman nutsedgeungu yang tumbuh daripada umbi pada peringkat awalnya ditanam dengan kepadatan 40, 80, 160 dan 320tanaman m bersama-sama lada hitam di dalam pot komersial sederhana bergaris pusat 35-cm, dengan keadaanpengairan dan pembajaan yang tidak terhad. Tiga hingga empat-peringkat-daun nutsedge ungu dan empat-peringkat-daun tanaman lada hitam telah disiram dengan D. hingginsii dalam 0.5% Metamucil, suatupembawa: rawatannya cuma pembawa sahaja, 104 conidia mt1 + pembawa, atau 10* conidia ml1 + pembawa.Secara signifikan, nutsedge ungu pada kesemua umbi yang padat mengurangkan hasil lada hitam tanpakehadiran D. hingginsii. Peratus hasil lada hitam menyusut lebih tinggi dalam rawatan bersama dengan 10*conidia mt1. Walau bagaimanapun, peratus kesusutan hasil lada hitam adalah sangat kecil jika dirawatdengan D. higginsii pada 106 conidia ml1 berbanding kawalan tanpa tumbuhan berumput. Secara signifikan,kadar perkembangan penyakit dalam rawatan bersama 1& conidia mt1 (V; = 0.113 0.123) lebih cepatberbanding yang dirawat bersama 10* conidia ml-1 (r° = 0.049 0.050). Pada 1(F conidia mt1, D. higginsiimengurangkan pencampuran nutsedge, memberi kawalan yang lebih tinggi pada nutsedge, dan meningkatkanhasil lada hitam berbanding kawalan berumput.

ABSTRACT

Greenhouse studies were conducted to evaluate the effect of the fungal pathogen, Dactylaria higginsii, on purplenutsedge interference with 'Capistrano' pepper (Capsicum a n n u u m ) . Purple nutsedge plants established fromtubers were planted at initial densities of 40, 80,160, and 320 plants m2 with pepper in 35-cm diam pots witha commercial potting medium, under nonlimiting fertilization and irrigation conditions. Three to four-leaf-stagepurple nutsedge and four-leaf-stage pepper plants were inoculated by spraying D. higginsii in 0.5% Metamucil,a carrier; the treatments were carrier only, 10* conidia ml1 + carrier, or 1& conidia conidia ml1 + carrier. Purplenutsedge at all tuber densities significantly reduced pepper yield in the absence o/D. higginsii. Percentage yieldloss of pepper was greater in treatment with 10* conidia mt1. However, percentage yield loss of pepper wasnegligible in treatments with D. higginsii at l(f conidia ml1 when compared to the non-weedy control. Thedisease progress rate was significantly faster in treatments with l(f conidia ml1 (r(; = 0.113 - 0.123) comparedto 10* conidia ml1 (rc - 0.049 - 0.050). At l(f conidia mt1, D. higginsii reduced nutsedge interference,provided greater nutsedge control, and increase pepper yield compared to weedy checks.

INTRODUCTION crops particularly early in the growing seasonPurple nutsedge is rated as one of the world's and heavy infestation of purple nutsedge canworst weed and has been reported in more than cause high yield loss in vegetable crops. Al-70 countries. It competes and interferes with though (chemical) herbicides inhibit the growth

B. KADIR, R. CHARUDATTAN, W.M. STALL, and TA. BEWICK

of the weed, adverse environmental factors andplant-growth stages at the time of application actagainst the effect of the herbicide (Gricher et al.1992). Several other nonchemical methods havebeen used, but none have provided acceptablecontrol. Long-term, sustained control of purplenutsedge has been difficult to achieve.

Research has recently commenced into theuse of a bioherbicide to reduce interference bypurple nutsedge in cropping systems. Dactylariahigginsii a fungal pathogen of purple nutsedgehas been reported to be capable of controllingthis weed (Kadir and Charudattan 1996, Kadir etal. 1997a; 1997b). However, its potential toreduce nutsedge interference in cropping sys-tem has not been studied. Therefore, the objec-tives of this research are: 1) to determine theeffective inoculum concentration needed to re-duce interference from the purple nutsedge and2) to determine the effect of D. higginsii on theinterference of purple nutsedge on pepper.


Experimental Method

The experimental method used in this study wasthe additive series approach. In this method,the density of one species (usually, called theindicator crop) is held constant and the densityof the other species (the weed) is varied. Sincethe latter is added into the first of this bipartiteseries, this approach is called the additive series.This system uses the response of the first speciesin fixed density as an indicator of the relativeaggressiveness or competitive ability of the sec-ond species to the first. This system is applicablein cropping systems with encroaching weeds andin intercropping systems (Cousens 1990; Nickelet al. 1990).

Purple Nutsedge Interference

The experiment was carried out in a greenhousein spring 1996 and repeated in autumn 1996,using transplants pepper cv 'Capistrano' as theindicator crop. A mixture of pepper and purplenutsedge were grown in 30 cm (diam) x 10 cm(height) pots filled with 0.07 ms of commercialpotting medium (Metro Mix 220, Scott-SierraHorticultural Product Co., Maryville, OH.) con-sisting of horticultural vermiculite, Canadianspaghnum peat, and horticultural perlite. Eachpot contained one transplant of pepper and oneof the following purple nutsedge densities: 0, 40,80, 160, and 320 tubers per m2. Plants in pots

were watered by drip irrigation three times dailyto stimulate soil moisture in the field. Soilfertility was maintained by adding water-solublePeters Professional All Purpose Plant Food(20:20:20 + Trace Elements, Spectrum Group,Div. of United Industries Corp., St Louis, MO)at the recommended rate of 3.785 liters of solu-tion (9.5 g/3.785 liters water) for 0,09 meter2

bed, every two weeks.

Fungal Inoculation

Inoculum used in this experiment was producedin trays on a thin layer of PDA (Kadir 1997).Three inoculum concentrations were used: 0[0.5% Metamucil (w/v), used as a hurnectant; asa control); 104 conidia/ml with 0.5% Metamucil(w/v); and 10f) conidia/ml with 0.5% Metamucil(w/v). One hour before the plants were inocu-lated, they were misted for 5 min to wet the leafsurfaces. The 4-leaf old pepper plants and 3-4-leaf old purple nutsedge were inoculated byspraying the conidial suspension with an aerosolsprayer until the excess fluid dripped off thefoliage. Starting 6h. after inoculation, the green-house misters were turned on for 5 min at every6h. interval for the first 24h. to maintain leafwetness. This was to ensure that D. higginsii,which requires a dew-duration period of at least12h. for disease development, would be able toinfect purple nutsedge under greenhouse condi-tions.

Data Collection

Disease severity was assessed every five days usingthe Horsefall Barratt scale (Horsefall and Barratt1945), modified by Kadir (Kadir 1997). Thevalues of the total portion of disease were trans-formed by using the Gompertz model transfor-mation (Berger, 1981) of the form:

Gompit y = - In (- ln(y))to linearize the disease progress curve. The areaunder the disease curve (AUDPC) was calcu-lated from this linearized curve using the equa-tion (Campbell and Madden, 1990):

Pepper was harvested at 50 and 65 days aftertransplantation and the yield was recorded asfruit weight (in gram) per plant. Pepper fruitswere harvested twice, since the yields during thefirst harvest did not show any expected trend.The data from the first and second harvest were


EFFECT OF DACTYIARIA HIGGINSII ON PURPLE NUTSEDGE INTERFERENCE WITH PEPPER

i <I

80 Control

104 conidia/ml

106 conidia/m!

100 150 200 250 300

Initial purple nutsedge density (tuber/m )

Fig. 1. Effect of inoculation of purple nutsedge with D. higginsii on the percentage yield loss ofC. annuum. Eachdata point represents the mean value from two trials each with four replicates. Control = noninoculated control;10* conidia ml1 = inoculated with 10* conidia ml1 at the rate of 90 ml m2; and Iff conidia ml1 = inoculatedwith 1& conidia mV at 90 ml m2.

pooled and recorded as the total yield per plant.Final tuber numbers of purple nutsedge wererecorded at the final harvest time (65 days aftertransplantation), from each pot. The tubersand the bulbs were separated after washing thesoil from the roots and rhizomes. Both wererecorded as tubers. The shoot plus tuber biomasswas determined at harvest time by weighing theshoots and tubers after they were dried at 75°Cfor 5 days. These parameters represent weed-growth components.

Statistical Analysis

The study was a factorial experiment with twofactors (tuber densities as the main factor andinoculum concentration as the sub-factor). Theexperiment had a randomized complete blockdesign with four replications. Mean values offour replications were used for statistical analy-sis. Orthogonal contrasts of the log inoculumconcentration and tuber densities, and of theslopes of the linear regression models, was per-formed to determine the individual effect oftuber density and inoculum concentration andtheir interactions on weed-growth componentsand crop yield. Linear regression of AUDPCagainst yield was done to determine their rela-tionship.

RESULTS

Homogeneity of variance among treatments werenoted in the levels of control of the weed-growthcomponents and disease severity of Dactylarialeaf blight on inoculated purple nutsedge fromboth trials. The data on weed growth compo-nents and disease severity, the latter expressedas the AUDPC, were therefore combined andaveraged over both trial dates.

Effect ofD. higginsii on weed-growth componentsand pepper yield

The initial planting density of tubers had asignificant effect on shoot and tuber dry weightof purple nutsedge in noninoculated controland in treatments where plants were inoculatedwith 104 conidia/ml (Table 1). The final shootand tuber dry weight of purple nutsedge in-creased with increasing purple nutsedge tuberdensity. Exception was the treatment in whichthe purple nutsedge plants were inoculated withD. higginsii at 106 conidia/ml. The final shootand root dry weight were significandy reducedin these treatments regardless of initial plantingdensities of tuber compared to the non-inocu-lated weedy control and treatments wherepurple nutsedge plants were inoculated with 104

conidia/ml.


B. KADIR, R. CHARUDATTAN, W.M. STALL, and T.A. BEWICK

TABLE 1Effect of inoculum concentration of D. higginsii and tuber densities on growth of

purple nutsedge when planted together with pepper (Capsicum, annuum)*.

QuadQuadQuadQuadQuadQuadQuad

logl o £loglogtd,td,td,

Contrast

cone,cone,cone,cone,cone.cone.cone.

td b=td -td =td -

= 0- 104

= 10"

4080160320

conidia/ml.conidia/ml.

Shoot dry weight

Mean (g)

23.1366.6374.6090.4291.9794.66

4.26

F-value

129.25***1115.02***1080.20***1538.85***775.77***692.60***

0.82NS d

Tuber dry weight

Mean (g)

31.2772.3877.1584.2196.4296.685.63

F-value

128.21***643.17***665.58***889.00***803.95***692.60***

1.38NS

Final tuber number

Mean (no.)

52.96115.50119.17128.37151.28155.10

5.63

F-value

4.38***288.95***308.47***432.06***386.25***297.62***

0.18NS

a Values are the average of two trials, each with four replicatesbtd = tuber density/m2

c***P < 0 0 0 0 1

dNS = Not significant

The slope comparison for relationship ofthe weed-growth components of purple nutsedgewith initial planting densities of tubers is shownin Table 2. The slopes of the non-inoculatedcontrol and treatments where purple nutsedgeplants were inoculated with 104 conidia/ml werecomparably similar, but were significantly lowerin treatment where purple nutsedge plants wereinoculated with 106 conidia/ml.

The percentage of yield loss of pepper wassignificantly high even at 40 tubers/m2 (19.07%for the control and 15.42% for 104 conidia/ml.The application of 104 conidia/ml of D. higginsiidid not have any significant effect in reducingthe yield loss of pepper. The percentage yieldloss of pepper was significantly reduced irrespec-

tive of tuber densities, when purple nutsedgewere inoculated with 106 conidia/ml. This couldbe explained by the reduction in weed growthcomponents (explained earlier).

Effect ofD. higginsii on AUDPCPurple nutsedge plants inoculated with 104

conidia/ml developed low levels of diseasecompared to plants inoculated with 106 conidia/ml. Almost all of the plants in the 10° conidia/ml treatments died. Secondary spread of D.higginsii from the previously diseased leavescaused subsequent infection on the regrowth,thus very little or no regrowth were observed.

The disease severity of the inoculated plantswas expressed as the AUDPC (Table 3). The

TABLE 2Slope values and comparisons of slopes from linear regression of growth components of purple

nutsedge and the initial tuber densities of purple nutsedge in pepper recorded 65 days afterinoculation with D. higginsii

Slope values

Treatments

Control104 conidia/ml10e conidia/ml

Control vs 104

Control vs 10"ID4 vs 10°

Shoot dry weight (g)

1.021.110.05

NS*

***

Tuber dry weight(g)

1.201.140.06

Contrasts of slope values

NS******

Final tuber numbers

2.712.520.05

NS******

aNS = Not significant.»*** = P< 0.001.

86 PERTANIKA J. TROR AGRIC. SCI. VOL. 23 NO. 2, 2000

EFFECT OF DACTYIAIUA HIGGINSII ON PURPLE NUTSEDGE INTERFERENCE WITH PEPPER

TABLE 3Area under the disease progress curve (AUDPC) and disease progress rate

(r() on purple nutsedge plants inoculated with D. higginsii?

Densities(tuber/m2)

4080160320

4080160320

Inoculum concentration(conidia/ml)

104104104104

106106106106

AUDPCb

1456.41452.51447.11442.3

5647.55887.55975.05962.5

0.0490.0470.0500.049

0.1130.1120.1170.123

a Fungus was applied at two inoculum levels and the treatment consisted of fourinitial densities of purple nutsedge tubers and pepper as indicator crop.

b AUDPC was calculated for disease severity from the means of two trials, each withfour replicates.

r Disease progress rate was calculated by using the Gompertz model (Berger,1981).

AUPDC values of treatment where purplenutsedge plants were inoculated with 104 co-nidia/ml were lower compared to AUDPC val-ues of treatment where purple nutsedge plantswere inoculated with 106 conidia/ml. The dis-ease progress rates (rc) of the treatment wherepurple nutsedge plants were inoculated with 104

conidia/ml (rG = 0.047 - 0.050) was slower com-pared to the apparent infection rates (r(; = 0.112- 0.123, Table 3) of the experiment where pur-ple nutsedge plants were inoculated with 106

conidia/ml.

TABLE 4Slope values and comparisons of slopes fromlinear regression of percentages of yield loss

of C. annuum on initial tuber densities ofpurple nutsedge recorded 65 days after

inoculation with D. higginsiL

DISCUSSION

Treatment

Control104 conidia/ml106 conidia/ml

Control vs 104

Control vs 106

104 vs 106

Slope values

0.750.740.06

Contrasts of slope valuesNSa

*#*b

* * *

A NS = not significant*» *** = p < 0.001

D. higginsii did not infect pepper. This wasexpected as this fungus had been previouslydetermined to be host specific to Cyperus spp.(Kadir and Charudattan 1999). Infection wasobserved on purple nutsedge in the control, dueto cross-contamination but the level of infectionwas below 5% severity. This low level would notaccount for any significant effect on the yield ofpepper or the final weed-growth components ofpurple nutsedge. The final weed-growth com-ponents of purple nutsedge were influenced bythe initial planting density of tubers, however,these components were significantly reduced intreatments where nutsedge plants were inocu-lated with 10G conidia/ml of D. higginsii. Thenutsedge plants in these treatments were se-verely diseased. Tubers from the diseased plantresprouted, but the growth was suppressed. Thisfinding is contradictory to the report by Marambe(1996) who found that purple nutsedge, evenwhen completely defoliated, tends to increaseshoot and tuber numbers. However, his studywas done in the absence of a crop, unlike ourstudy which was carried out in the presence ofpepper plant. The shading provided by thevigorously growing pepper plant probably helpedto maintain humid conditions and promote dis-ease development with severe secondary infec-tion.


B. KADIR, R. CHARUDATTAN, W.M. STALL, and T.A. BEWICK

The faster disease progress rate (rG) in treat-ments inoculated with 106 conidia/ml could beexplained by the higher inoculum level, com-bined with the presence of pepper that shadedpurple nutsedge plants, predisposing them toinfection by D. higginsii. The high humidityunder the crop canopy provided a conduciveenvironment for disease development. Moreo-ver, shading appeared to have caused purplenutsedge to produce weaker plants, which wereless competitive and more prone to infection byD. higginsii. Bantillan et al. (1974), Patterson(1982), Santos et al. (1997), and William andWarren (1975) found that shading reduced lightavailable to the parent purple nutsedge plants.Thus, thinner and weaker shoots were producedthat were less competitive.

D. higginsii has the potential to reducethe interference of purple nutsedge in a peppercropping system when applied at 10° conidia/ml. However, the field efficacy of this fungusunder different cropping systems needs to bestudied further.

ACKNOWLEDGEMENTSWe thank Jay Harrison for advice on statisticalanalysis. This research, based on the first au-thor's dissertation, was supported by funds pro-vided by the USDA Special Grants in TropicalAgriculture, Caribbean Basin AdministrativeGroup (CBAG) Grant No. 94-34135-0649 andthe University of Florida. The senior authorthanks Universiti Putra Malaysia for the grant ofa scholarship and a study leave for his doctoralresearch at the University of Florida.

REFERENCESBANTILAN, R.T., M.C. PALADA, and R.R. HARWOOD.

1974. Integrated weed management: Keyfactors affecting crop-weed balance. Philip-pines Weed Sci. Bull. 1: 14-36.

BERGER, R.D. 1981. Comparison of the Gompertzand logistic equations to describe diseaseprogress. Phytopathology 71: 716-719.

CAMPBELL, CL. and L.V. MADDEN. 1990. Introduc-tion to Plant Disease Epidemiology, p. 532. NewYork: John Wiley 8c Sons.

COUSENS, R.D. 1990. Considerations in designarid analysis of competition experiments.WSSA Abstracts 30: 297.

GRICHAR, W.J., P.R. NESTER, and A.E. COLBERN.

1992. Nutsedge (Cyperus spp.) control inpeanuts (Arachis hypogaea) with imazethapyr.Weed Technol 6: 393-400.

HORSFALL, J.G. and R.W. BARRATT. 1945. An

improved grading system for measuring plantdisease. Phytopathology 35: 655.

KADIR, J, 1997. Development of a bioherbicidefor the control of purple nutsedge. Ph.DDissertation. University of Florida. 150 p.

KADIR, J. and R. CHARUDATTAN. 1996. Dactylariahigginsii (Luttrell) M.B. Ellis: A potentialbioherbicide for nutsedges (Cyperus spp.).WSSA 36:49.

KADIR, J. and R. CHARUDATTAN. 1999. Dactylariahigginsii, a fungal bioherbicide agent forpurple nutsedges (Cyperus rotundu). Biologi-cal Control 17: 113-124.

KADIR, J.B., R. CHARUDATTAN, R.D. BERGER, W.M.

STALL, and BJ. BRECKE, 1997a. Field efficacyDactylaria higginsii for control of purplenutsedge. Phytopathology 87: 49

KADIR, J.B., R. CHARUDATTAN, W.M. STALL, and

T.A. BEWICK. 1997b. Effect of Dactylariahigginsii on the interference of purplenutsedge with tomato and pepper. Phytopa-thology 87: 50.

MARAMBE, B. 1996. Effect of defoliation ongrowth and physiological developments intubers of purple nutsedge (Cyperus rotundusL.>. J. Agron. Crop Sci. 176: 323-329.

NICKEL, S.E., S.R. SIMMONS, C.C. SHEAFFER, and

S.R. RADOSEVICH. 1990. Addition series ap-proach to assessing competition in a smallgrain-alfalfa companion crop community.Crop Sci. 30: 1139-1141.

PATTERSON, D.T. 1982. Effects of shading on thegrowth of purple and yellow nutsedges. Proc.So. Weed Sci. Soc. 34: 230.

SANTOS, B.M., J.P. MORALES-PAYAN, W.M. STALL,

and T.A. BEWICK. 1997. Influence of tubersize and shoot removal on purple nutsedge(Cyperus rotundus) regrowth. Weed Sci. 45:670-673.

WILLIAM, R. D. and G. F. WARREN. 1975. Compe-tition between purple nutsedge and vegeta-bles. Weed Sci. 23: 317-323.

Received : 10 Mac 1999Accepted: 30 Oktober 200

88 PERTANIKAJ. TROP. AGRIC SCI. VOL. 23 NO. 2, 2000


Macronutrients Distribution and Cycling of Pineapple Plantedon Tropical Peat

O.H. AHMED, M.H.A. HUSNI, MM. HANAFI, S.R. SYED OMAR, and A.R. ANUARDepartment of Land Management, Faculty of Agriculture,

Universiti Putra Malaysia43400 UPM, Serdang, Selangor, Malaysia

Keywords: Nutrient cycling, pineapple, tropical peat, macronutrients

ABSTRAK

Kajian ini mengkuantitikan kemasukan, kehilangan, penahanan (tanah) dan pengambilan serta pengembalianPf K, Ca, dan Mg untuk pengurusan sisa nenas yang dibakar dan tidak dibakar. Rawatan yang digunakanadalah: sisa daun dikeluarkan dan tiada pembajaan (LRRNF), sisa daun dibakar dengan tiada pembajaan(LRBNF), sisa daun dikeluarkan dan diikut pembajaan (LRRF) dan sisa daun dibakar dan pembajaandilakukan (LRBF). Nitrogen, P dan Kdibekalkan dalam bentuk urea (46.00% N), batuan fosfat China (CPR14.00% P) dan muriate of potash (MOP 49.80% K) pada kadar 701.04, 35.56 dan 556.56 kg N, P dan Kper hektar mengikut turutan. Simulator hujan digunakan untuk menghitung larian permukaan pada plot sisadibakar sebelum penanaman. Sampel tanah pula diambil pada kedalaman 0-5, 5-25 dan . 25 sm sebelum,semasa dan selepas peringkat-peringkat pembajaan. P, K, Ca dan Mg yang tersedia diestrak menggunakankaedah dxviasid. Kaedah subtraksi pula digunakan untuk menganggar P, K, Ca dan Mgyang dilarut lesap (kgper ha). Pada peringkat matang, sampel tumbuhan diambil pada setiap rawatan dan dibahagikan kepada akar,batangy daun, buah, jambul dan tangkai serta berat keying dan kandungan P, K, Ca dan Mg di tentukan.Kandungan P, K, Ca dan Mg pada tanah, bahagian tumbuhan dan air hujan ditentukan melalui kaedah'molybdate blue' dan spektrofotometer penyerapan atom (AAS). Penambahan P, K, Ca dan Mg daripada baja,abu dan presipitasi bagi LRBF dianggarkan pada 54.25, 816.68, 103.31 dan 23.54 kg per ha. Rawatan LRRF(pembajaan dan presipitasi) pula dianggarkan pada 35.56 P, 576.05 K, 100.17 Ca dan 4.93 Mg kg per ha.Anggaran kehilangan P, K, Ca dan Mg pada rawatan LRBF adalah pada 18.44, 300.45, 66.06 dan 8.63kg per ha manakala pada rawatan IURF, nilai-nilai adalah pada 23.19, 244.88, 45.79 dan 5.49 kg per ha.Larut lesap merupakan punca utama kehilangan P, K, Ca dan Mg bagi kedua-dua jenis pengurusan dan inidapat dirujukkan dengan frekuensi pembajaan yang kurang sesuai. Satu keseimbangan positif P, K, Ca danMg dapat direkodkan untuk LRBF, 46.00% P, 28.005 K, 20.00% Ca dan 27.00% Mg dapat dikitarsemulaselepas penanaman. Bagi rawatan LRRF pula, keseimbangan positif P, K, Ca dan Mg diperhatikan. Lebihkurang 60.00% P, 20.00% K, 13.00% Ca dan 36.47% Mg digunasemula untuk rawatan ini.

ABSTRACT

This research quantifies P, K, Ca and Mg inputs, losses, retention in soil, and uptake and returns for burnt andunburnt pineapple residue in management practices. Treatments used were: leaves residue removed and nofertilization (LRRNF), leaves residue burnt and no fertilization (LRBNF), leaves residue removed and fertilization(LRRF), and leaves residue burnt and fertilization (the usual practice) (LRBF). Nitrogen, P and K were appliedin the farms of urea (46.00% N), China phosphate rock (CPR 14.00% P) and muriate of potash (MOP49.80% K) at the rates of 701.04, 35.56, and 556.56 kg N, K, and Pper ha respectively. Rainfall simulatorwas used for surface runoff measurement on burnt plots before planting. Soil sampling at the depths of 0-5, 5-25 and . 25 cm were done before planting, during and after fertilization stages. Extractable P, K, Ca and Mgwere extracted using the double-acid method. The subtraction method was used to estimate P, K, Ca and Mgleached (kg per ha). At maturity, plants were sampled from each treatment and partitioned into roots, stem, leaves,fruit, crown and peduncle, and the dry weights, ofP, K, Ca and Mg contents determined. Molybdate blue methodand atomic absorption spectrophotometer were used in determining P, K, Ca and Mg in soil, plant parts and

O.H. AHMED, M.H.A. HUSNI, M.M. HANAFI, S.R. SYED OMAR and A.R. ANUAR

rainwater, K, Ca and Mg additions from fertilizer, ash and precipitation for LRBF were estimated at 54.25,816.68, 103.31 and 23.54 kg per ha, and those of LRRF (fertilizer and precipitation) were 35,56, 516.05,100.17, and 4.93 kg P, K, Ca, and Mg per ha, respectively. The estimated amounts of P, K, Ca and Mg lostunder LRBF were 18.44, 300.45, 66.06 and 8.63 kg per ha and in the case of LRRF, the losses were 23,19,244.88, 45.79 and 5.49 kg per ha. Leaching was the major source of P, K> Ca and Mg loss for both practicesand this was attributed to inappropriate fertilization frequency. A positive balance of P, K, Ca and Mg wasrecorded for LRBF, 46.00% P, 28.00% K, 20.00% Ca and 27,00% Mg which could be recycled after cropping.In the case of LRRF, a positive balance ofP, K and Ca was observed. About 60.00% P, 20.00% K, 13.00%Ca and 36.47% Mg get recycled for LRRF.

INTRODUCTIONCultivation of pineapple (Ananas comosus) onpeat in Malaysia has been in existence for abouta century (Selamat and Ramlah 1993). The cul-tivation currently practiced on large-scale ini-tially started on small-scale basis with no fertiliza-tion. After the extensive and comprehensivesurvey of the pineapple cultivation (Dunsmore1957), the need to apply balanced fertilizers forthe growth and production of pineapple sur-faced. Consequently, various fertilizer recom-mendations (Tay 1972; Tay 1973) for varietieslike Singapore Spanish, Masmerah and Johorelwere put forward. The recommendations werenutrient response oriented and as such none ofthe studies attempted or gave due cognizance ofnutrient losses through leaching and runoff,nutrient retention after cropping not to men-tion inputs from ash and precipitation.

Perhaps when it became obvious that theprevious recommendations have oudived theirusefulness, a study was initiated to determinethe right requirement of N, P, and K of thesevarieties on peat (Selamat and Ramlah 1993).Again, physical and physiological parameters werethe focus of the study. Even though the studywas conducted at a time when nutrients additionthrough burning crop residue, precipitation,leaching, and surface runoff losses and themechanism of nutrient retention in organic soilshad advanced, a holistic approach like nutrientbalance was not considered.

With the ever increasing cost of fertilizers,plus the ever increasing awareness of the pollut-ing effects that excess fertilizer applications haveon the environment, there is a need to quantifythe movement of nutrients into, within andwithout pineapple cultivation system. A broadbased approach of this kind referred to as nutri-ent budget can be used as a tool in estimatingthe nutrient requirements of pineapple andhence help in the reduction of polluting effectsthat excess fertilizer applications may have on

the environment. The study was conducted toquantify P, K, Ca and Mg inputs, losses, reten-tion (soil), and returns for burnt and unburntpineapple residue management practice.


The experiment was carried out at SimpangRengam Pineapple Estate, Johor, Malaysia. Thisplace is a representative area for pineapple cul-tivation on peat in Malaysia. Treatments usedwere: (i) leaves residue removed and no fertili-zation (LRRNF), (ii) leaves residue burnt andno fertilization (LRBNF), (iii) leaves residueremoved and fertilization (LRRF) and, (iv) leavesresidue burnt and fertilization (the usual prac-tice) (LRBF). The experimental unit was indi-vidual plants planted in 4 m x 12 m plot. Alto-gether 300 pineapple plants were planted ineach plot having a randomized complete blockdesign (RCBD) with 4 replications. The 1997haze incident in South-East Asia has drawn pub-lic attention and concern to the polluting effectof open burning of crop residue on the environ-ment, hence the inclusion of treatments i andiii.

Nitrogen, P and Kwere applied in the formsof urea (46.00% N) China phosphate rock (CPR-14.00% P) and muriate of potash (MOP-49.80%K) at the rates of 701.04, 35.56, and 556.56 kg ofN, K, and P per ha, respectively. These rates arethe rates used by the pineapple estate.

Prior to the start of the experiment, infiltra-tion rate was measured in all the burnt plotsusing the double ring infiltrometer. Before firstfertilization, water samples from surface runoffon the burnt plots using rainfall simulator(Kamphorst 1987) were collected, filtered andanalyzed for P, K, Ca and Mg. Throughout thestudy, P was analyzed using molybdate bluemethod (Murphy and Riley 1962) and K, Ca,and Mg were analyzed using the atomic absorp-tion spectrophotometer.

90 PERTANIKA J. TROP. AGRIC. SCI. VOL. 2S NO. 2, 2000

MACRONUTRIENTS DISTRIBUTION AND CYCLING OF PINEAPPLE PLANTED ON TROPICAL PEAT

K, Ca, and Mg concentrations were multi-plied by volume of runoff collected within 3minutes per 0.0625 m2 (area covered by the baseof the rainfall simulator). Simple proportion wasthen used to convert the values to kg per habasis. Kilogram per ha P, K, Ca and Mg multi-plied by the number of runoff days gave thetotal amounts of P, K, Ca and Mg (kg per ha)lost through surface runoff between the periodat which the experiment was started and the firstfertilizer application. Surface runoff days referto the rainy days on which runoff occurred andthese days were selected based on the assump-tion that surface runoff occurs when rainfallintensity is higher than infiltration rate (Jackson1989).

Peat core samplers of diameter 7.50 cmwere used to collect peat samples at the depthsof 0-5, 5-25 and .25 cm for bulk density deter-mination. These sampling depths were also usedto monitor leaching loss. Soil samples were takenbefore planting, fertilization and after fertiliza-tion stages. At the fertilization phase, sampleswere taken 3 weeks after fertilization so as toensure uniform distribution and dissolution ofthe fertilizers. Subsequent post fertilization sam-ples were taken bimonthly until the end of theexperiment. Rainwater was collected from threerain gauges located at three different places inthe estate at every sampling period stated andanalyzed for P, K, Ca, and Mg.

Some plants of the different treatments wererandomly selected and tagged when visual dif-ferences between the treatments began showingat the third month. Nutrients accumulation inleaves with time was monitored right from thethird month of planting until plants were har-vested by taking D-leaf and the contents of P, K,Ca, and Mg determined. D-leaf is the longestand easily identifiable leaf that provides a reli-able and sensitive indication of pineapple nutri-tional status (Py et aL 1987). At maturity, plantsfrom each treatment were randomly sampledand partitioned into roots, stem, leaves, pedun-cle, fruit and crown. These parts were ovendried at 60°C and their dry weights taken. Dryashing (single dry ashing) was adopted for theextraction of P, K, Ca, and Mg., K, Ca, and Mgdistribution were determined by multiplying theweight of plant parts by their respective concen-trations. The products of P, K, Ca and Mgdistribution per plant and plant density gave thetotal P, K, Ca, and Mg kg per ha in the distinctparts of the pineapple.

K, Ca, and Mg in soil were extracted usingthe double acid method (0.05M HC1: 0.025MH2S04) with soil to solution ratio of 1:10 (modi-fied from Van Lierop et aL 1980). The reasonbehind the modification of the extractionmethod were: (i) A dilute soil extractant helpsin eliminating the possibility of the neutraliza-tion of the extracting solution through reactionwith the soil and possibly reaction of Ca and Mgcoming from the burnt crop residue plus arti-facts in the soil, and (ii) Prolonged extractiontime plus wider extraction ratio helps in mini-mizing the effects of rewetting time variability ofdry peat (Van Lierop et aL 1980).

Weight of soil per ha at .25 cm (i.e. ap-proximately 25-50 cm) multiplied by the respec-tive concentrations of P, K, Ca and Mg gave thetotal amounts of kg P, K, Ca, and Mg per ha atthat depth (leaching zone). Weight of soil perha was estimated by multiplying a hectare vol-ume of soil at .25 cm with the correspondingbulk density. The amounts of P, K, Ca, and Mgleached per ha at each sampling period werecalculated using the subtraction method shown:TNL = NAF - NAU; where TNL = Total nutrientleached, NAF = Nutrient accumulated at .25cm in fertilized plots, and NAU = Nutrient accu-mulated at .25cm in unfertilized plots (modi-fied after Pomares-Gracia and Pratt 1978). Forthe burnt practice, leaching loss at samplingperiods started from the first sampling afterburning until the end of the cropping periodand that of the unburnt started from the firstsampling after first fertilization till the end ofthe cropping period. The depth of .25 cm waschosen as leaching zone because it was assumedthat nutrients at this zone are beyond the reachof pineapple roots as roots grow laterally (Py etaL 1987).

RESULTS AND DISCUSSIONGeneral Information

The bulk density at the depths of 0-5, 5-25, and.25 cm were 0.16, 0.23 and 0.13 g per cm3

respectively. The infiltration rate of 0.2 cm perminute was obtained. The initial status of theextractable P, K, Ca, and Mg were relatively high(Table 1). Since the land has been under culti-vation for the past 30 years, there is the ten-dency that residual accumulation might havetaken place. Insignificant difference in P, K, Ca,and Mg contents in the soil were observed forthe plots assigned the intended treatments:



LRRNF, LRBNF, LRRF and, LRBF before thestart of the experiment (Table 1).

The general accumulation of the extract-able P, K, Ca, and Mg for LRRF and LRBF at 0-5 cm (Table 2) may be due to inappropriatefertilizer application frequency. Besides the lessmobile nature of P, the high accumulation of Camight have also contributed to the P accumula-tion at 0-5cm (Cogger and Duxbury 1984).

Nutrients Addition

The sources of P, K, Ca, and Mg additions werefertilizer, ash, and precipitation with fertilizercontributing the highest amounts of P, K, andCa for LRBF and LRRF (Table 3). For LRBF,ash contributed the highest amount of Mg withits P and K contribution second to fertilizer. TheCa from ash was relatively low as compared tothose of fertilizer and precipitation (Table 3).Precipitation contributed no P, however, its con-tribution of K, Ca, and Mg was relatively high(Table 3) compared to the findings ofMohammad (1981) and Veneklass (1990). Possi-bly, the distance of the experimental site fromthe sea (about 20 km), the haze problem (dur-ing the experiment) in South-East Asia and thepossibility of some ash suspension during andafter burning may account for the difference.The total amounts of P, K, Ca, and Mg fromfertilizer, ash, and precipitation addition to the

pineapple nutrient cycle were 54.25, 816.48,103.31 and 23.54 kg per ha for LRBF and 35.56,576.05 100.17 and 4.93 kg per ha for LRRF(Table 3).

Nutrient Losses

Leaching was the major source of P, K, Ca, andMg loss under LRBF and LRRF. In the case ofLRBF, second to leaching loss was through fruitharvest (Table 3). Apart from Mg where the lossthrough fruit harvest was third to leaching, P, K,and Ca loss through residue removal was secondto leaching followed by fruit harvest. Phospho-rus, Ca, and Mg loss through surface runoff wasrelatively low. The total amounts of P, K, Ca, andMg lost under LRBF were 18.44, 300.45, 66.06and 8.63 kg per ha and those of LRRF were23.19, 244.88, 45.79 and 5.49 kg per ha (Table3).

Except for Mg where leaching occurred af-ter fertilization, leaching loss of P, K, and Caoccurred before, during and after fertilization.Generally, the bulk of K, Ca, and Mg got leachedat the post fertilization stage. The reason beingthat, more of P, K, Ca, and Mg got accumulatedat the fertilization phase especially during thelast fertilization (263rd day after planting) - aperiod where the plants were nine months old.At that stage, nutrient requirement of pineappleis generally lower than during or early growth

TABLE 1The initial status of extractable P, K, Ca and Mg at three different

depths before experimentation

Treatments

LRRNF

LRBNF

LRRF

LRBF

Depth (cm)

0-55-25. 25

0-55-25. 25

0-55-25. 25

0-55-25. 25

P

482020

402020

532025

432020

K

mg/kg

540446383

503400382

472460423

535520427

Ca

1397835940

1418920865

1347800850

1370775928

Mg

906085

886058

835863

1077073

Note: Insignificant difference between treatments at same depths usingLSD <; 0.05 was observed.

92 PERTANIKA ). TROR AGRIC. SCI. VOL. 23 NO. 2, 2000

9gH2M

31H

;RIC

.SC

I

a0

i

Samplingdays

48

144

263

365

417

466

LRNF

88

40

53

33

18

23

I

P

LRBNF

115

48

45

33

13

25

LRRF

113

110

2700

1450

1145

793

TABLE 2Extractable P, K, Ca and ]

LRBF

200.00

193

2733

1207

590

500

LRNF

555

520

320

135

260

245

K

LRBNF

1395

448

373

182

228

266

Mg at various sampling

Extractable nutrients

LRRF

563

885

3300

574

265

290

LRBF

kg]

1758

1040

3093

443

368

270

LRBF

ha-I

2718

1628

1945

1222

1105

1127

stages

Ca

LRBNF

4163

1865

2265

2205

1925

1900

•:

LRRF

2198

2130

7175

4810

4838

1970

LRBF

4446

2143

7843

4873

4528

3536

j

"2,\ •••' '

LRBF

195

130

253

78

78

77

1

LRBNF

383

198

283

235

175

93

Vig

LRRF

183

180

635

233

120

95

- 3

LRBF

348

220 r

655 '

181 £

123

95

2CD

0

r>

D C

YC

I

uOO

%

*TTED O

N T

RO

PIG

*LL PE

AT

CO00


TABLE 3P, K, Ca and Mg inputs, losses, returns and retention (soil) for burnt and unburnt practices

InputsFertilizerAshPrecipitation

Total (a)

Losses (b)FruitLeaves residueLeachingRunoff (ash)

Total (b)

Input-Loss (c)

Uptake (d)

AmountRetained insoil = c - d

P

35.5618.690.00

54.25

5.720.00

11.571.15

18.44

35.81

16.10

19.71

LRBF (leaves burnt)K

557.09240.43

18.96

816.48

71.610.00

183.6945.15

300.45

516.03

142.94

373.09

Ca

62.483.14

37.69

103.31

2.260.00

59.154.65

66.06

37.25

7.39

29.86

MgLRRF (leaves

P

kg/ha

0.4118.60

4.53

23.54

2.030.005.201.40

8.63

14.91

3.96

10.95

35.560.000.00

35.56

4.976.52

11.700.00

23.19

12.37

7.43

4.94

K

557.090.00

18.96

576.05

50.3251.16

143.400.00

244.88

331.17

65.00

266.17

removed)Ca

62.480.00

37.69

100.17

2.612.66

40.520.00

45.79

54.38

6.14

48.24

Mg

0.410.004.53

4.93

1.621.272.600.00

5.49

-0.56

2.83

-3.39

stage (Py et al. 1987) therefore, with annualrainfall of about 1917 mm coupled with the verylow clay (Stevenson 1994), the potential for P,K, Ca, and Mg lost through leaching was high.

Nutrients Removal and ReturnsUnder LRBF, the total amounts of P, K, Ca, andMg taken up (roots, stem, leaves, peduncle andcrown) from fertilizer, ash and precipitationthat can be recycled were 16.10, 142.94, 7.39,and 3.96 kg per ha. Those of LRRF (roots andstem) were 7.43, 65.00, 6.14, and 2.83 (Table 3).It must be noted that, since leaves, peduncleand crown for LRRF are not recycled, theirnutrients removal was considered loss and wereexcluded in this section.

Nutrients Retention after Cropping

After taking into account nutrients returns andlosses, the amounts (kg per ha) of P, K, Ca, andMg from inputs (fertilizer, ash, and precipita-tion retained) in the soil (at 0-5 and 5-25cm)after cropping were 19.71, 373.09, 29.86 and10.95 for LRBF and 4.94, 266.17, 48.24 and 2.27kg per ha for LRRF (Table 3).

Unutilized P, K, Ca, and Mg under LRBFwere relatively high. K and Ca retained underLRRF were also high but with low P. This low Pmay partly be due to residue removal as itcontributed about 28% (second to leaching loss)of the total P lost. It is therefore anticipated thatif this practice goes on for some time, more Pwill be depleted and hence rescheduling of fer-tilizer program will be inevitable. The negativebalance of Mg (Table 3) recorded for LRRF maybe attributed to the unaccountability of Mg ad-dition through stem and roots decompositionduring the cropping period as these parts underLRRF are normally not removed from the field.However, for the sake of accountability if it isconsidered or assumed that the amount of Mgtaken from the inputs (fertilizer and rainfall) bythese parts is proportional to the amount re-turned through decomposition, about 2.83 kgMg per ha is recycled and hence the 2.83 kg Mgper ha balances the deficit.

CONCLUSIONSThe existing fertilization regime particularly forK in pineapple cultivation on peat for the burntand unburnt pineapple residue management


MACRONUTRIENTS DISTRIBUTION AND CYCLING OF PINEAPPLE PLANTED ON TROPICAL PEAT

practices is inappropriate. There is therefore theneed to reschedule the present fertilizer regime.Perhaps the last fertilization needs to be stopped.

ACKNOWLEDGEMENTSWe are thankful to Mr. Lee Sing Kim, Mr. KohSoo Koon, and Mr Faisol Abdul Ghani ofSimpang Rengam Pineapple Estate, PeninsulaPineapple Plantation, Johor, Malaysia for thepartnership in the collaborative research. Wealso acknowledge the financial support of theNational Council for Scientific Research andDevelopment, Malaysia and the encouragementof Universiti Putra Malaysia (UPM) in researchand development. We also appreciate the assist-ance of the staff of the Soil Fertility Laboratory.

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DUNSMORE, J. R. 1957. Pineapple fertilizer inMalaya. Malay Agric J 40: 159.

FUNAKAWA, S. *L YONEBAYASSHI, J.F. SHOON, and

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JACKSON, IJ. 1989. Climate, Water and Agiculture inthe Tropics. Essex: Longman.

KAMPHORST, A.C. 1987. A small rainfall simulatorfor the determination of soil erodibility.Netherlands J. Agric. Sd. 35: 407-415.

MOHAMAD, T.D. 1981. Nutrient cycle in rubber plan-tations. In RRIM Training Manual on Soils,Management and Nutrition of Hevea. RubberResearch Institute of Malaysia.

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POMARES-GRAGIA, F. and P.F. PRATT. 1987. Recov-ery of 15N-labelled fertilizer from manuredand sludge-amended soils. Soil Set. Soc. Am,J. 42: 717-720.

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sponse of pineapple cv. Gandul to nitrogen,phosphorus, and potassium on peat soils inMalaysia. ACTA Horticulturae 334: 247-254.

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John Wiley and Sons, Inc.

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VAN LIEROP, W., Y. A. MARTEL, and M. P. CESCAS.

1980. Optimal soil pH and sufficiency con-centrations of N, P and K for maximumalfalfa and onion yields on acid organicsoils. Can. J. Soil Set. 45: 1-11.

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Received: 22 March 2000Accepted: 8 July 2000



Effects of Food Plants on Development of Spirama retorta(Lepidorptera: Noctuidae)

AHMAD SAID SAJAP and ABD. KARJM ABD. SAMADDepartment of Forest Management

Universiti Putra Malaysia43400 UPM. Serdang, Selangpr, Malaysia

Key-words: Spirama retorta, Acacia mangium, Acacia auriculiformis, Acacia crassicarpa, Paraserianthesfalcataria

ABSTRAKPembesaran Spirama retorta (Lepidoptera: Noctuidae) larva yang diberi makan daun tiga spesies Acacia, iaituA. mangium, A. auriculiformis dan A. crassicarpa, dan Paraserianthes falcataria telah dinilai di makmaLLarva yang didedahkan kepada daun A. crassicarpa dan P. falcataria kesemuanya matipada instar pertama.Lebih daripada 64 % larva yang memakan daun A. mangium dan A. auriculiformis mencapai peringkatpupa. Jangkamasa larva pada daun A. auriculiformis ialah 22.10 hart manakala pada A. mangium ialah24.83 hari. Jan^iamasa pupa dari A. auriculiformis ialah 10.51 hari dan dari A. mangium ialah 11.32hari. Ini menghasilkan rama-rama dewasa yang hidup selama 36,51 dan 37.94 hari. Walaupun padakeseluruhannya, angkaubah pembesaran tidak signifikan, rama-rama betina yang pada peringkat larvamemakan daun A. auriculiformis menghasilkan lebih banyak telur daripada yang memakan A. mangiumiaitu 412 telur// dari A. auriculiformis dan 255 telur// dari A. mangium. Kajian ini menunjukkan daunA. auriculiformis dan A. mangium sesuai untuk pemakanan larva S. retorta. Oleh ituf spesies ini bolehmenjadi sumber altematif makanan penting untuk dinamik populasi rama-rama ini jika ketiadaan tumbuhanhos asli.

ABSTRACTDevelopment of Spirama retorta (Lepidoptera: Noctuidae) larvae fed on foliage of three Acacia, spp., namely A.mangium, A. auriculiformis and A. crassicarpa, and Paraserianthes falcataria was assessed in thelaboratory. The larvae did not survive when fed on either A. crassicarpa or P. falcataria. More than 64%reached pupal stage when fed on A. auriculiformis and A. mangium. The larval period was completed in 22.10and 24.83 days when the larvae fed on A. auriculiformis and A. mangium foliage, respectively. The averagepupal period xuas 10.51 and 1132 and, the resulting adults lived for 36.51 and 37.94 days on A.auriculiformis and A. mangium, respectively. Even though the overall development variables were notsignificantly different, females from larvae fed A. auriculiformis had a significantly higher fecundity than thosefemales from A. mangium. A total of 412 eggs// was recorded from those fed A. auriculiformis as comparedto 255 eggs// on A. mangium. This study thus shows that foliage of A. auriculiformis and A. mangiumprovided a suitable diet for S. retorta larvae. As such, these species may serve as alternative food resourcesimportant in the population dynamics of the moth in the absence of indigenous host plants.

INTRODUCTIONThe declining supply of timber from naturalforests has led many tropical countries includingMalaysia replenish their timber resource byadopting a reforestation program involving plant-ing of fast-growing exotic species. In Malaysia,about 500,000 ha of unproductive forest hasbeen alienated for establishment of forest plan-

tations. To date, approximately 100,000 ha offorest plantations have been established. Ninetypercent of this was planted with Acacia mangium.While Gmelina arborea and Paraserianthes falcatariawere planted on a smaller scale.

A. mangium is a fast growing leguminoustree indigenous to Northern Australia, PapuaNew Guinea and Irian Jaya (Anon. 1983). The

AHMAD SAID SAJAP and ABD. KARIM ABD. SAMAD

tree can grow up to 30 m high with a straightbole measuring 40 cm in diameter at breastheight. It can be harvested for pulpwood in fiveto seven years or sawlog production in 12 to 15years. In addition to A. mangium, A. auriculifarmisand A. crassicarpa have also been the subject ofmany researches in Malaysia. Results from prov-enance trial plots indicated that these trees havethe potential to be grown for commercial plan-tations (Nor Aini et al. 1994; Kamis et al. 1995).

Even though trees like Acacia often performvery well when grown as exotics, they are, how-ever, prone to attack by diseases and insects. Todate, many indigenous insects have been re-ported to be associated with these Acacia andsome could pose serious threats to the planta-tions (Abe 1983; Hutacharern 1993; Chey 1996,Sajap et al 1997). One of these insects was arare moth, Spirama retorta (Lepidoptera:Noctuidae). The larvae of this insect were foundin an outbreak where they defoliated a one-yearold A. mangium stand in an area of 800 ha atGunung Besaut Forest Plantation, Sungkai, Perak.The biology of this insect was described by Sajapet al. 1996. Apart from A. mangium, no otherhost plant has yet to be associated with thisinsect in Malaysia. Albizzia lebbek was the onlyrecorded host plant elsewhere (Beeson 1961).

In this study, we examined the suitability ofthree Acacia spp. and P. falcataria for the devel-opment of S. retorta. Paraserianthes falcataria wasincluded as it was related to the reported hostplant, A. lebbek. This information is pertinent indetermining the host range of the insect in viewof its becoming a potential pest of Acacia spp.


Insect Rearing

A colony of S. retorta was established from larvaecollected from A. mangium plantation at GunungBesaut, Perak. The larvae were kept in 11 x 15x 25 cm plastic boxes provided with fresh A.mangium foliage. The foliage was changed every-day. When the larvae reached the fifth instar,vermiculite which acted as a substrate for pupa-tion, was added into the box. The pupae werecollected, sexed and surface-sterilized with 1%sodium hypochlorite. Five pairs of male andfemale pupae from the same cohort were heldin a cage for adult emergence, subsequent mat-ing and oviposition. The oviposition cage con-sisted of a cylindrical wire mesh, 9 x 12 cm,

internally lined with a netting cloth which wasused oviposition site. Ten percent honey solu-tion in a cotton-plugged vial and a slice of veryripe papaya were placed in the cage and servedas food sources. Eggs collected from the colonywere kept in 9 cm petri dishes for hatching.

Feeding experiment

Test Plants

A. mangium, A. auriculiformis and A. crassicarpa,and P. falcataria plant materials were obtainedfrom provenance trial plots located at UniversitiPutra Malaysia, Serdang.

Experimental Procedure

Fresh foliage was placed in 9 cm petri disheslined with two pieces of moistened filter papers.One neonate was introduced into each petridish. The foliage and the filter papers werechanged daily and weekly, respectively.Vermiculite was added into the petri dishes whenthe larvae reached the end of the fifth instar.Growth and development parameters: mortality,molting period, pupal weight and size of thehead capsule, were recorded. Faeces defaecatedthroughout the larval stages were collected daily,oven-dried at 80°C for 24 h, cooled and weighed.Newly emerged adults were sexed and paired.Each pair was placed in a cage for oviposition.Eggs were collected and counted daily. A total of100 larvae per treatment in four replicates, 25per replicate, were used in this study. All experi-ments were carried out in a room at 27 - 32°Cand 70 - 80% RH.

Data Analysis

Statistical analysis of all the developmental vari-ables was conducted by t-test ( a • 0.05)

RESULTS

Larval Mortality

The result from this feeding study shows that S.retorta could feed and develop on foliage of A.mangium and A. auriculifarmis. They failed tofeed on A. crassicarpa and P. falcataria and diedin the first stadium. The total mortality forlarvae fed on A. mangium and A. auriculiformiswere 36% and 31%, respectively, with more than22% dead before reaching the third instar. Allthe larvae that pupated emerged into adults(Table 1).


EFFECTS OF FOOD PLANTS ON DEVELOPMENT OF SP1RAMA RETORTA (LEPIDOPTERA: NOCTUIDAE)

TABLE 1Developmental time (days) and percent

mortality of S. retorta larvae fed on A.auriculiformis and A. mangium foliage

Stage

I

II

III

IV

V

VI

VII

Pupa

Adult

Egg

A. auriculiformisdays * %

3.07 ± 0.26a

3.12 ± 0.32a

3.46 ± 0.53a

3.48 ± 0.53a

3.91 ± 0.61a

6.39 ± 1.90a

7.52 ± 0.72a

10.51 ± 1.85a

/10.11 ± 0.90a

? 9.11 ± 0.51a

4.00 ± 0.87a

13.00

9.18

2.23

2.59

2.66

5.48

1.00

0

-

-

A. mangiumdays * %

3.11 ± 0.31a

3.36 ± 0.55a

3.64 ± 0.57a

3.61 i 0.58a

4.06 ± 0.94a

5.19 ± 1.41a

7.81 ± 0.82a

11.32 ± 1.24a

9.60 ± 0.51a

7.70 ± 0.68a

4.20 ± 0.84a

15.00

10.00

3.00

3.00

3.00

4.00

1.00

0

-

-

* Means in the same row followed by the sameletter are not significantly different (a =0.05)

Developmental Period

The development time of S. retorta larvae fed onA. mangium and A. auriculiformis is shown inTable 1. The larval period was completed in22.10 ± 2.42 days and 24.83 ± 2.71 days when thelarvae fed on A. auriculiformis and A. mangiumfoliage, respectively. The larvae went througheither six or seven instar before pupation. OnA. mangium, 22% and 78% attained their pupalstage after the sixth and seventh instars, respec-tively. On A. auriculiformis, 56% attained pupalstage after the sixth instar and 44% after theseventh instar. The average pupal period was10.51 ± 1.85 days and 11.32 ± 1.24 days when thepreceeding larvae were fed on A. auriculiformisand A. mangium, respectively. The longevity ofthe adults emerging from larvae previously fedon A. auriculiformis stages was relatively shorterthan those fed on A. mangium. With A.auriculiformis their longevities were 10.11 ± 0.90days and 9.11 ± 0.51 days for the females andthe males, respectively. With A. mangium thelongevities were 9.60 ± 0.51 days and 7.70 ± 0.68days for the females and the males, respectively.

Head Capsule Size and Pupal Weight

Head capsule size and pupal weight were notsignificantly different for individuals fed on ei-

ther foliage. The width of head capsule increasedfrom 0.30 mm in the first instar to about 3.00mm in the seventh instar (Table 2). The result-ant pupae also had similar sizes and weights.The pupal wieght and length from larvae fed onA. auriculiformis were 0.90 ±0.11 g and 2.65 ±0.10 mm, respectively and those fed on A.mangium attained pupal weight and length of0.89 ± 0.10 g and 2.66 ± 0.13 mm, respectively.

TABLE 2Means of head capsule width (mm) ofS. retorta larvae fed on A. mangium and

A. auriculiformis foliage

InstarA. mangium

(mm)*A. auriculiformis

(mm)*

I

II

III

IV

V

VI

VII

0.30 ± 0.00a

0.54 ± 0.05a

0.86 ± 0.10a

1.40 ± 0.18a

2.07 ± 0.21a

2.69 ± 0.23a

2.92 ± 0.16a

0.30 ± 0.00a

0.55 ± 0.50a

0.85 ± 0.06a

1.40 ± 0.12a

2.08 ± 0.14a

2,75 ± 0.24a

2.94 ± 0.17a

*Means in the same row followed by the sameletter are not significantly different (a =0.05)

Faeces Production

S. retorta consumed about the same amount ofeither A. auriculiformis or A. mangium foliageexcept in the seventh instar (Table 3). This wasshown by the amount of faeces defaecatedthroughout the larval period. The weight offaeces obtained from the larvae in the seventhstadium feeding on A. auriculiformis was signifi-cantly higher than those larvae feeding on A.mangium foliage. The total amount faeces def-ecated by a larva fed on A. auriculiformis and A.mangium was 773.49 and 724.71 mg, respectively.

Fecundity

The number of eggs laid by females previouslyfed on A. auriculiformis (412//) was almost dou-ble those females previously fed on A. mangium(255//) foliage during their larval stages. Thedaily oviposition rates of the moths is shown inFigure 1. Moths emerging from A. auriculiformis-reared larvae laid an average number of eggsvaried from 50 on the first day, reached its

PERTANIKA j . TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000 99

AHMAD SAID SAJAP and ABD. KARIM ABD. SAMAD

TABLE 3Means of faecal weight (mg) produced by

S. retorta larvae fed on A. mangium andA. auriculiformis foliage

In star

I

II

III

IV

V

VI

VII

A. mangium(mg)*

8.98 ± 0.98a

10.93 ± 1.00a

24.21 ± 5.72a

50.88 ± 9.59a

137.41 ± 59.88a

296.79 ± 92.66a

195.52 ± 70.51a

A. auriculiformis(mg)*

8.58 ± 0.90a

11.02 ± 1.10a

24.19 ± 5.92a

48.28 ± 10.43a

137.23 ± 58.45a

305.22 ± 94.31a

238.97 ± 83.55b

* Means in the same row followed by the sameletter are not significantly different (a =0.05)

maximum of 115 on the second day and droppedto 38 eggs on the seventh day. Although asimilar trend of oviposiotion pattern was alsoobserved on moths emerging from A. mangium-reared larvae but the average number of eggslaid daily was lower. On the first day, 43 eggswere laid. The number increased to 90 on thethird day and dropped to 22 on the fifth day.All eggs hatched in three days with hatchingrates exceeding 90% for both batches.

140

120

Fig. 1. Fecundity ofS. retorta moths previously fed onA. mangium and A. auriculiformis foliageduring the larval stage

DISCUSSION

Host plants play an important role in growthand development of an insect. The resultantimpact of the nutritive value of the plant con-

sumed by the insect could be reflected in thelarval development rate, pupal weight, femalefecundity, survivorship and behaviour of the in-sect (Beck and Reese 1976; Slansky 1982; Hagenet al 1984.). In this study, even though thelarvae initiated feeding, indicated by the manybiting marks on P. falcataria foliage, they, how-ever, failed to continue feeding and died in thefirst stadium. The rejection of the foliage by thelarvae could be due to the absence of tokenstimuli or the presence of deterrent chemicalsthat inhibit them from further feeding on thefoliage despite the very tender foliage texture(Ehrlich and Raven 1964). This phenomenoncommonly occurred in insects that were ex-posed to non-host plants (Hough and Pimentel1978). When offered foliage of A. crassicarpa, S.retorta larvae did not initiate feeding and left nobiting marks on the foliage. This could be attrib-uted to the toughness of the foliage that led toa 100% mortality at the early stage.

Even though, there were no significant dif-ferences in the overall developmental periodand growth parameters between individuals fedon A. auriculiformis and A. mangium, larvae fedon A. auriculiformis apparently developed rela-tively faster than on A. mangium. The larvae thatdeveloped through seventh instar defaecatedmore faeces when fed on A. auriculiformis thanon A. mangium. Consequently, the adults had arelatively longer reproductive period and laid ahigher number eggs than those previously rearedon A. mangium foliage. This result suggests thatA. auriculiformis presumably has a superior nutri-tive value and thereby served a better host plantthan A. mangium.

In summary, the foliage of A. auriculiformisand A. mangium provided a suitable diet for 5.retorta larvae. As such, these tree species mayserve as food resources important in the popu-lation dynamics of the moth in the absence ofthe indigenous host plants.

ACKNOWLEDGEMENT

We would like to thank Mr. Yaacob Abd. Wahaband Mrs. Aida Murshidi of the Forest Entomol-ogy Laboratory, Universiti Putra Malaysia, fortheir help in the conduct of the experiment.

REFERENCES

ABE, IC 1983. Plantation forest pests in Sabah.FRC Publication No. 8.


EFFECTS OF FOOD PLANTS ON DEVELOPMENT OF SPIRAMA RKfORTA (LEPIDOPTERA: NOCTUIDAE)

ANON. 1983. Mangium and other fast growingacacias for humid tropics. National ResearchCouncil. National Academy Press. Washing-ton DC.

BECK S.D. and J. C. REESE. 1976. Insect-plantinteractions: nutrition and metabolism.Recent Advances in Phytochemistry. 10: 41-92.

BEESON, C. F. C. 1961. The Ecology and the Control

of the Forest Insects of India and the Neighbour-ing Countries, 2nd ed. Government of India.

CHEY, V. JL 1996. Forest Pest Insects in Sabah.Sabah Forest Record No. 15. Sabah ForestDepartment, Sandakan.

ERHLICH, P.R. and P.H. RAVEN. 1964. Butterfliesand plants. Evolution 18: 586-603.

KAMIS AWANG, NOR AINI ABD. SHUKOR and ABD.

LATIF SENIN. 1995. Two-year performance ofAcacia crassicarpa provenances at Serdang,Malaysia. Pertanikaf. Trop. Agric. Sri. 18: 177-181.

HAGEN, KS., R.H. DADD and J. REESE. 1984. The

food of insects. In Ecological Entomology, ed.C. B. HufTaker and R. L. Rabb, p. 79-112.New York: John Wiley.

HOUGH, J.A. and D. PIMENTEL. 1978. Influence of

host foliage on development, survival andfecundity of the gypsy moth. Environ. Entomol.7: 97-102.

HUTACHARERN, C. 1993. Insect pests. In Acariamangium: Growing and Utilization, ed. KamisAwang, D. Taylor, p. 163-202. MPTS Mono-graph Series No. 3. Bangkok. Thailand.

NOR AINI ABD. SHUKOR, KAMIS AWANG, P.

VENKATESWARLU and ABD. LATIF SENIN. 1994.

Three-year performance of Acaciaauriculiformis at Serdang, Malaysia. PertanikaJ. Trop. Agric. Sc. 17: 95-102.

SAJAP, A.S., A. W. YAACOB and M. AIDA. 1997. An

outbreak of Ericeia subcinerea Snellen (Lepi-doptera: Noctuidae), a new pest of Acaciamangium. MAPPS Newsletter 2: 5.

SAJAP, A.S., A. W. YAACOB and M. AIDA. 1997.

Biology of Spirama retorta (Lepidoptera:Noctuidae), a new pest of Acaria mangiumin Peninsular Malaysia. / . Trop. For. Sc. 10:167-175.

SLANSKY, JR. F. 1982. Insect nutrition: Anadaptationist perpective. Fla. Entomol 65:45-71.

Received: 27 April 2000Accepted: 30 November 2000


PertanikaJ. Trop. Agric. Sci. 23(2): 103 -112 (2000) ISSN: 1511-3701© Universiti Putra Malaysia Press

Quality Assessment of Local and Franchise Beef and Chicken Burgers

A.S. BABJI, M.N. NURI, J. SUHERMAN and M.Y. SERI CHEMPAKADepartment of Food Science and Nutrition, Faculty of Life Sciences

Universiti Kebangsaan Malaysia 43600 Bangi, Selangor

Keywords : burger, local, franchise, microbiology, composition, meat content

ABSTRAK

Enamjenama burger lembu dan ay am, tigajenama burger lembu francais dan duajenama burger ayamfrancaistelah dinilai dari segi kandungan proksimat, kandungan daging dan mioglobin, warna (nilai L, a, b) dankandungan mikrobiobgi iaitu Kiraan Jumlah Plat (CFU/gm), Kiraan Koliform dan Escherichia coli (MPN/gm), Kiraan Staphylococus aureus (CFU/gm) dan kehadiran Salmonella sp. Kesemua burger lembu francaismempunyai kandungan protein dan kelembapan yang lebih tinggi (kecuali burger C) dan kandungankarbohidrat yang lebih rendah dari jenama tempatan. Didapati tiada perbezaan yang nyata (p > 0.05) dalamkandungan aba, lemak dan serabut kasar antara burger lembu francais dan jenama tempatan. Kebanyakanburger ayam jenama tempatan mempunyai kandungan protein dan kelembapan yang lebih rendah dankandungan lemak, serabut dan karbohidrat yang lebih tinggi berbanding dengan burger ayam francais. Didapatitiada perbezaan yang nyata (p > 0.05) dalam kandungan abu antara burger ayam jenama tempatan danfrancais. Kesemua burger lembu mempunyai kandungan mioglobin dan daging yang rendah (< 65 %) kecualiburger Al, Fl dan Gl. Burger ayam El, Fldan burger francais B mempunyai kandungan daging yang lebihtinggi (> 65%) berbanding dengan yang lain. Kesemua burger ayam dan lembu mempunyai nilai 'L' yang lebihtinggi iaitu antara 45.13% hingga 53.68% dan 62.75% hingga 72.48% masing-masing kecuali Fl yanglebih gelap. Burger lembu jenama tempatan mempunyai nilai 'a' lebih tinggi berbanding dengan francais dankesemua burger ayam mempunyai nilai 'a' yang rendah kecuali Fl yang lebih merah. Kiraan Jumlah Plat,Kiraan Koliform dan E. coli yang rendah didapati di dalam semua sampel burger. Kiraan S. aureus dalamsampel burger lembu dan ayam berjenama tempatan adalah lebih tinggi daripada francais iaitu antara 2 hingga11 CFU/gm sampel dan antara 6 hingga 22 CFU/gm sampel masing-masing. Tiada kehadiran Salmonella spdapat dikesan dalam semua sampel burger.

ABSTRACT

Six brands of local beef and chicken burgers, three brands of franchise beef and two brands of franchise chickenburgers xoere evaluated for proximate composition, myoglobin and meat content, colour (L, a, b values) andmicrobiology composition i.e. Total Plate Count (CFU/gm), Coliform and Escherichia coli Counts (MPN/gm),Staphylococus aureus Count (CFU/gm) and presence of Salmonella sp. All franchise beefburgers had higherprotein and moisture contents (except burger C) and lower carbohydrate content than the local brands. Nosignificant differences (p > 0.05) in fat, ash and crude fibre contents were observed between local brands andfranchise beef burgers. Most local brands of chicken burgers had lower levels of protein and moisture and higherlevels of fat, fibre and carbohydrate than the franchises. No significant differences (p > 0.05) in ash content wasobserved between the local brands and franchise chicken burgers. All beef burgers had low myoglobin and meatcontents (<65%) with the exception of Al, Fl and Gl burgers. Chicken burgers, El, Fl and franchise burgerB had higher meat content (>65%) than the others. All beef and chicken burgers had higher 'L' values whichranged between 45.13% to 53.68% and 62.75% to 72.48% respectively except Fl which was darker. Localbrands of beef burgers had a higher 'a' value compared to the franchises and all chicken burgers had a low 'a"value except Fl which was redder. Low Total Plate Count, Coliform and E. coli counts were detected in all burgersamples. S. aureus counts in most local brands of beef and chicken burger samples were higher than the franchiseswhich ranged from 2 to 11 CFU/gm sample and 6 to 22 CFU/gm sample respectively. Salmonella sp was notpresent in all burger samples.

A.S. BABJI, M.N. NURI, J. SUHERMAN and M.Y. SERI CHEMPAKA

INTRODUCTION

An increase in the demand for fast food inMalaysia is due to the changing habits of theconsumers in the 90's; it is convenient, easy toserve and eat, and suitable for those always 'onthe run'. The western type of meat productswhich are currently adopted and manufacturedin Malaysia are mosdy beef and chicken burgersand frankfurters. Burgers have became one ofthe most popular fast food in Malaysia and therehas been a rapid growth in local production ofburgers in the past few years. In 1985, the giantforeign franchises were MacDonald's, Wendy'sand the A&W chain of restaurants (Babji andLetchumanan 1989). This trend was followed bylocal producers and many franchise companieswere formed such as Ramly, Yeo Hiap Seng,Purnama and Saudi. However, there are majordifferences between local burgers and thosefranchised. Differences include organolepticproperties, chemical composition, formulations,nutritional composition and overall acceptanceof these burgers by consumers.

The inherent high price for premium qual-ity animal protein have induced local producersto manufacture meat products of a lower qualityfor the mass consumption by the local popula-tion. Various unconventional raw materials andnon-meat ingredients were utilized for furtherprocessing with only a low percentage of meat asthe raw material being blended into the formu-lation. In processed meat production, premiummeat cuts are seldom used. The utilization ofunconventional raw materials and plant proteinin meat products affects the chemical and nutri-tional composition and also the microbiologicalquality of the products. Under the Food Regula-tion of Malaysia 1985, burgers are classified asmanufactured meat which must contain not lessthan 65% meat, 1.7% nitrogen and not morethan 30% fat in organic combination. Babji et al(1984, 1985) and Babji (1988) have reportedvarious aspects of nutritional composition, useof food binders and additives, and the process-ing and quality control standards in the manu-facturing of local beefburgers in Malaysia. Manyof the local manufacturers paid little attentionto the nutritional as well as quality aspects of theproducts. Quality control in the processed meatindustry is still unsatisfactory. There are alsoproblems encountered in the establishment ofminimum standards and specifications for suchnew products (Babji 1988). Information on theraw material composition, microbiological status

and quality control aspects, particularly more soon the non-conventional raw materials from thelivestock industry is poorly documented. Thequality of locally produced and franchise burg-ers should be monitored from time to time toensure that the products the minimum require-ments of the standards and specifications, andare of acceptable quality to the consumers.

This study was carried out to observe thequality of the local and franchise beef andchicken burgers by determining the proximatecomposition, myoglobin and meat content andmicrobiological aspects. It is necessary to ascer-tain the quality of products consumed by theconsumer. This study also provides informationto satisfy the needs of consumers who demandmeat products that are nutritions, well-balancedand safe from toxic and microbial contamina-tions.

MATERIALS

The analyses were carried out on six local brandsof beef burgers i.e. Angus, Biffi, Fika, Ramly,Purnama and Saudi, and six local brand chickenburgers i.e. Ramly, Ayamas, Ayam Dinding, Fika,Purnama and Saudi. Most of which are availablein the local supermarkets. The three types offranchise beef burgers were obtained from MacFood Services, A&W and MBF Food Divisionand two types of franchise chicken burgers wereobtained from Mac Food Services and MBF FoodDivision. The franchise burgers (beef andchicken) were labelled A, B and C and localburgers (beef and chicken) were labelled Al,Bl, Cl, Dl, El, Fl, Gl, HI to fulfill the compa-nies requirement for product anonymity.

The burger samples were analysed (dupli-cate) for proximate composition, colour in termsof lightness ('L'), redness (V) and yellowness('b'), myoglobin and meat content. The micro-biology quality of the burger were tested bydeterminating Total Plate Count (CFU/gm),Conform and E. coli counts (MPN/gm) 5. aureuscount (CFU/gm) and the presence / absence ofSalmonella sp.

METHODS

Proximate Analysis

Proximate analyses were carried out using AOAC(1984) methods which included protein deter-mination using Kjeldahl method, fat extractionvia Soxhlet method, crude fibre determinationusing digestion with sulphuric acid, moisturedetermination by drying the sample for 16 - 18


QUALITY ASSESSMENT OF LOCAL AND FRANCHISE BEEF AND CHICKEN BURGERS

hours at 100 - 102°C in oven and the ash byashing the sample at 550°C for 9 hours in fur-nace oven. Carbohydrate content was determinedby substracting the value from the total (100%)minus the percentages of other contents.

Physico-chemical Analysis

The lightness ('L'), redness ('a') and yellowness(*b*) values for colour determination were meas-ured using a chromameter (MinoltaChromameter Model CR - A70).

The myoglobin content was determined byusing Poel Cyano Method (Topel, 1949). A 10g sample was homogenized for 2 minutes incold water mixed with X ml IN H2SO4 in awaring blender. (X = ( pH sample - 5 ) x0.35). The pH of meat samples was determinedusing the AOAC method (1980). The homoge-nate was centrifuged at 3000 rpm for 2 minutesin a polyethylene tube (50 ml) using the MSEDesk centrifuge. The supernatant obtained wastransferred to a 50 ml tube and heated slowly toreach a temperature of 54°C after which it wassoaked in a water bath to reach 25°C. Thehomogenate was placed in a 100 ml beaker andthe pH brought to 7.2 using Na2CO3. The ho-mogenate was transferred back to a 50 ml tubeand centrifuged for 10 minutes at 2500 rpm.The supernatant was filtered into a 50 ml Erlen-meyer flask and 2-3 small crystals of potassiumferricyanide was added. Absorbance was read at540 nm using the Spectronic 20. Calculation ofmyoglobin (Mb) was derived by Poel-Cyano(Topel, 1949):mg Mb / g wet tissue = absorbance x 7.50

Meat Content

The meat content for the burger samples wasdetermined by using the myoglobin contentsobtained earlier using the Poel Cyano Method(1949). A standard curve was constructed usingmyoglobin content of beef : soy protein orchicken : soy protein mixtures with standardizedpercentage of meat i.e. beef / chicken : soy ;100/0, 80/20, 60/40, 40/60, 20/80, 0/100. Thebeef used in the mixtures was Indian beef as itis commonly used in the burger industry. Thechicken meat used in chicken soy protein mix-ture was from the defatted breast meat. The soyprotein used was soy protein isolate 500 E ob-tained from local suppliers. The meat content ofthe burger samples were obtained from thesestandard curves using their myoglobin contentswhich had been determined earlier.

Microbiological analysis

The following analyses were carried out usingprocedures described by Oxoid (1979); TotalPlate Count (TPC), Coliform count (MPN),E. coli (MPN), S. aureus count and presence/absence of Salmonella sp. A 10 gm sample ofeach material (frozen) was homogenized asepti-cally in a stomacher bag with 90 ml sterileRinger solution using a stomacher (ModelSeward BA 7021). The homogenous sample so-lution was used for the determination of TotalPlate Count, Coliform, E, coli and S. aureus count.Total Plate Count was carried out using thepour plate technique, with Plate Count Agar(PCA, Oxoid) and incubated at 37°C for 48hours. For the Coliform count, MacConkey brothmedia containing Neutral Red as an indicatorwas used. The number of presumptive positivetubes (5 tubes) were counted and refered to theMPN Table. For E. coli count (MPN), positivetubes from Coliform count were tested in pairs,using Eijkman test (Mac Conkey broth) andIndole test (Tryptone water). Only tubes show-ing positive results for both tests are consideredpresumptive positive for E. coli. For 5. aureuscount, Baird Parker Agar (Oxoid) was used whichwas enriched with Egg Yolk Tellurite Emulsion(Oxoid). The innoculum was spread on thesurface of the agar and incubated at 37°C for 24- 48 hours. Salmonella sp (25 gram sample) wasisolated using pre-enriched buffered peptonewater, followed by selective enrichment inSelenite Cystine Broth (SCB, Oxoid) andTetrathionate Broth (TTB, Merck) and finallyselective agar medium, Brilliant Green Agar(BGA, Oxoid) and Bismuth Sulphite Agar (BSA,Difco). The presence of Salmonella sp was con-firmed with Triple Sugar Iron Agar (TSI, Oxoid)and Lysine Iron Agar (LIA, Oxoid).

RESULTS AND DISCUSSIONTable 1 showed the proximate composition oflocal brands and franchise beef burgers. Fromthe statistical analysis, there were significant dif-ferences (p < 0.05) in protein, moisture andcarbohydrate contents between the local brandsand franchise beef burgers. However, there wereno significant difference (p > 0.05) in fat, ash,and crude fibre contents. From Table 2, therewere significant differences (p < 0.05) betweenthe local brands and franchise chicken burgersin moisture, fat, protein, carbohydrate and crudefibre contents except in the ash.



TABLE 1Proximate composition of local and franchise beef burgers

Samples *

Local :AlBlClFlGlHI

Mean

Franchise :ABC

Mean

* Mean of

Samples *

Local :AlDlElFlGlHI

Mean

Franchise :AB

Mean

Protein

15.51 ± 0.9610.00 ± 0.7111.71 ± 0.6715.26 ± 2.4112.70 ± 0.6514.42 ± 0.84

13.27 ± 1.04

18.07 ± 0.6121.26 ± 0.1620.76 ± 0.34

20.03 ± 0.37

Fat

12.36 ± 1.1525.74 ± 0.6221.83 ± 0.8417.47 ± 0.9919.05 ± 0.0823.38 ± 0.19

19.97 ± 0.65

15.23 ± 0.3619.27 ± 0.4220.19 ± 0.17

18.23 ± 0.32

two samples/treatment

Proximate composition

Protein

12.67 ± 0.6913.96 ± 1.5314.38 ± 0.6615.66 ± 1.2513.33 ± 1.5415.54 ± 0.55

14.26 ± 1.04

22.74 ± 0.8818.20 ± 0.32

20.47 ± 0.60

Fat

23.05 ± 0.6612.72 ± 0.5415.26 ± 0.7121.02 ± 0.9416.27 ± 1.0023.55 ± 0.41

18.65 ± 0.71

5.86 ± 0.257.63 ± 0.63

6.75 ± 0.44

Percentage ( % )Moisture

57.41 ± 0.8245.26 ± 0.9747.16 ± 1.3449.10 ± 0.7255.06 ± 0.7345.32 ± 0.38

49.89 ± 0.69

61.61 ± 0.3256.89 ± 0.4956.42 ± 0.44

58.31 ± 0.42

TABLE 2

CHO

12.76 ± 0.0316.45 ± 0.2516.54 ± 0.6214.78 ± 0.5110.80 ± 0.6314.16 ±0.13

14.25 ± 0.36

2.77 ± 0.021.05 ± 0.030.11 ±0.02

1.31 ± 0.02

Ash

1.63 ± 0.292.02 ± 0.122.18 ± 0.152.85 ± 0.032.08 ±0.132.18 * 0.17

2.16 ± 0.15

1.53 ±0.160.83 ± 0.132.07 ± 0.08

1.48 ± 0.12

of local and franchise chicken burgers

Percentage ( % )Moisture

50.81 ± 0.2568.00 ± 0.3464.89 ± 0.4648.01 ± 1.3557.82 ± 1.5444.57 ± 0.61

55.68 ± 0.76

68.40 ± 0.4366.44 ± 1.08

67.42 ± 0.76

CHO

10.16 ± 0.882.06 ± 0.051.97 ± 0.32

11.50 ±0.619.09 ± 0.63

12.53 ± 0.13

7.89 ± 0.44

1.27 ± 0.035.69 ± 0.03

3.48 ± 0.03

Ash

1.54 ± 0.031.52 ± 0.191.94 ± 0.172.04 ± 0.051.85 ±0.112.08 ± 0.09

1.83 ±0.11

1.32 ± 0.281.69 ± 0.15

1.51 ± 0.22

Fiber

0.33 ± 0.010.53 ± 0.020.58 ± 0.020.54 ± 0.010.31 ± 0.010.54 ± 0.02

0.47 ± 0.01

0.79 ± 0.020.70 ± 0.020.45 ± 0.01

0.65 ± 0.02

Fiber

1.77 ± 0.091.74 ± 0.181.56 ± 0.031.77 ± 0.091.64 ± 0.061.73 ± 0.04

1.70 ± 0.08

0.41 ± 0.020.35 ± 0.02

0.38 ± 0.02

* Mean of two samples/treatment

Franchise beef burgers had higher proteincontent, ranging between 18.07% to 21.26%,compared to local brands which ranged from10.00% to 15.51%. For chicken burgers, theprotein level in franchise burgers was higherthan the local brands which were 22.74% and18.20% for franchise burger A and B respec-tively. Some local beef burgers were found tocontain high fat, (more than 21%) and carbohy-drate (more than 14%) contents but lower inprotein content. In local burgers with proteincontents ranging from 11% to 16%, it is obvious

that some of the meat protein have been re-placed by binders and fillers such as rusk,breadcrumbs, cereal, legumes and soy protein.This is reflected in the higher carbohydratecontents in local burgers. This was similar withthe HI, Al and Fl chicken burgers where thefat and carbohydrate contents were more than21% and 10% respectively and low in proteincontent. Babji et al. (1989) reported that manu-facturers in their efforts to cut cost, often usedmeat substitutes such as cereals, soy proteins,ground nuts and lately mechanically debonedmeat to formulate hamburgers.

106 PERTANIKA ). TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000


For Gl beefburgers and Dl and Gl chickenburgers, although they have low protein con-tent, their fat content was not as high as in theothers. However they had a higher moisturecontent which were 55.06%, 68.00% and 57.82%respectively. More water could be added to theburgers with the assistance of binders and fillerssuch as rusk, cereals, breadcrumbs, texturedvegetable protein and soy protein. The use ofcarbohydrate fillers add to the volume of theproduct since it absorbs water and binds wellwith the meat (Smith 1979). Carbohydrate andsoy protein also aid in increasing water holdingcapacity of the meat product (Wilner 1979). Soyprotein is popular because of its high waterholding capacity, good texture and bulkiness inweight when hydrated (Babji et al. 1989). Al-though the use of soy protein in meat and meatproducts is strictly regulated overseas, in Malay-sia, there is currently no specific regulation con-cerning its use in local meat products (Babji etal. 1984). Nevertheless, although the moisturelevel was high in franchise beef and chickenburgers including Dl and El burgers, the carbo-hydrate contents were low ranging from 0.11%to 5.69%.

Although there were no significant differ-ences in ash and crude fibre contents in beefburgers, the local brand had a higher ash con-tent but lower in crude fibre content whencompared with franchise beef burgers A and B.This was also the same for chicken burgers,where the level of ash and crude fibre werelower in some local brands. The presence ofspices for seasoning, high fibre carbohydrate,starches, cereals, legumes and soy protein couldincrease the ash and fibre contents in the burg-ers. The incorporation of mechanically debonedchicken meat in burgers also could increase theash content due to the presence of bone parti-cles and high calcium content. Method usingmyoglobin content can be used to quantitatethe meat content in meat products. Its inherentvariability in meat tissue is well-defined but itsconversion to cyanometmyoglobin from this pro-cedure reduces its heterogenous variability incomminuted meat samples (Babji et al. 1989).Figures 1 and 2 showed the standard curvesplotted from the myoglobin content in the beef: soy protein, and chicken : soy protein mixtureswhich have standardized percentages of meat.From these curves, the meat content for allburger samples were calculated based on the

0 10 20 30 40 50 60 70 80 90 100 110

% b««f (beef ; soy protein isolate mixtures)

Fig. 1. Standard curve for beef burgers using beef :soy protein isolate mixture

0 10 20 30 40 50 60 70 80 90 100 110

% beef (beef : soy protein Isolate mixture*)

Fig. 2. Standard curve for chicken burgers usingchicken meat : soy protein isolate mixture

myoglobin content. All franchise beef burgersand some local brands had lower meat contentsthan standard requirement (65% meat) for itranged from 59% to 63% (Table 3). Only Al, Fland Gl beef burgers had higher meat contents

TABLE 3Myoglobin and meat content in local and

franchise beef burgers.

Samples *

Local :AlBlClFlGlHI

Franchise :ABC

Myoglobin Content(mg/g sample)

3.32 ± 0.192.64 ± 0.302.55 ±0.142.86 ± 0.233.08 ± 0.202.70 ± 0.07

2.71 ± 0.362.71 ± 0.042.70 ± 0.05

Meat Content(%)

77.25 ± 4.9061.00 ± 7.2759.00 ± 2.7566.00 ± 5.4571.38 ± 4.3162.50 ± 2.20

62.13 ± 2.3262.13 ± L0461.98 ± 1.14




which ranged between 66% to 77%. Low meatcontent in some local beef burgers could ex-plain the low protein content in these burgers asthe addition of beef fat and carbohydrate maybe practised. Nevertheless, the franchise burgersalso had low meat contents but had higherprotein contents compared to other samples.This indicates that non-meat ingredients such assoy protein and caseinate which have high pro-tein content could have been added. To date,most beef imported from India, usually from thefore quarters. It is even cheaper than the im-ported soy protein isolate and concentrate, whichwould lead one to believe that manufacturerswould use more meat (at least 65%) so as not tocontravene the food regulation. Instead manu-facturers go for a formulation consisting of In-dian Beef (40-60%), soy proteins (10-30%),wheat/tapioca flours, mechanically debonedmeat and egg proteins to come up with the leastcost (Babji et al 1989).

Table 4 showed that most local brandchicken burgers and franchise chicken burger Ahad lower meat content (64.50%) compared tothe standard requirement (65% meat). Only Fl,franchise chicken burger B and El had highmeat contents and these burgers also had highprotein contents (Table 2). High protein con-tent and low meat content in HI and franchisechicken burger A indicated that there were ad-dition of high protein, non-meat ingredients inthe formulations.

Because of the lower amount of meat usedin some local products, producers probably haveto complement it with beef flavourings and col-

TABLE 4Myoglobin and meat content in local and

franchise chicken burgers.

Samples *

Local :AlDlElFlGlHI

Franchise :AB

Myoglobin content(mg/g sample)

2.45 ± 0.042.55 ± 0.342.65 ± 0.023.16 ± 0.152.42 ± 0.042.32 ± 0.05

2.61 ± 0.072.88 ± 0.03

Chicken meat(%)

62.50 ± 0.0964.50 ± 3.0467.00 ± 0.7780.63 ± 3.8460.50 ± 0.4858.00 ± 1.01

64.50 ± 0.0277.50 ± 0.95


ours to resemble meat. The use of food colour-ings in the manufacture of beef burgers is mainlyto camouflage the use of fillers such as soyproteins and carbohydrates. Fresh meat colouris related to the total heme myoglobin pigmentand biochemical condition (Desrosier 1977).From Table 5, no significant differences wereobserved (p > 0.05) for 'L' values but significantdifferences occurs for 'a' values between thelocal brand and franchise beef burgers. Al andFl beef burgers had a darker colour (high 'a'value); similar to the high myoglobin and meatcontents. For 'b' (yellowness) value, there weresignificant differences (p < 0.05) between thelocal brands and franchised beef burgers. Thishigh value for yellowness could be due to highfat content in the burgers.

TABLE 5The colour values (L-lightness, a-redness, b-yellowness) for local and franchise beef burgers

Samples *

Local :AlBlClFlGlHI

Franchise :ABC

L

47.89 ± 0.0353.68 ± 2.5348.14 ± 1.5543.39 ± 1.2052.75 ± 0.5351.92 ± 1.77

52.76 ± 0.8052.02 ± 1.2045.13 ± 0.20

Beef burgersa

+20.45 ± 0.29+21.89 ± 0.56+25.32 ± 1.44+31.78 ± 1.37+23.37 ± 0.98+23.64 ± 1.44

+6.38 ± 0.35+15.20 ± 1.36+5.38 ± 0.18

b

+15.86 ± 0.01+19.47 ± 0.33+11.43 ±0.79+17.43 ± 1.48

+15.55 ± 0.92

+16.38 ± 0.57+13.24 ± 0.55+12.57 ±0.25




Most of the chicken burgers had high L'values which ranged between 62.75 to 72.48except for Fl chicken burgers (Table 6). Flchicken burger was observed to have a reddercolour (a higher *a' value) compared to theother burgers. Generally there was no signifi-cant differences (p > 0.05) between the localbrands and franchise chicken burgers for 'L\ 'a'and 'b' values. Chicken meat is lighter and lessred in colour than beef or Indian beef especiallythe breast meat. The thigh meat is redder anddarker because of the muscles and high contentof myoglobin.

Tables 7 and 8 showed the Total Plate Count(TPC), Coliform, E.coli and S. aureus counts forall burger samples. TPC showed that the burgersamples meet the standards stipulated by theFood Regulation of Malaysia (1985) which statedthat the number of microorganisms in meat andmeat products must not exceed 106 per gramsample. TPC for local brand beef burgers wasvery low, in the range of 1 x 101 to 8 x 101 pergm sample. Higher TPC was found for franchisebeef burgers ranging 2 x 10* to 2 x 103 per gmsample. Similarly with the chicken burgers, thefranchise burgers had higher counts (9 x 102 to2 x 10s per gm sample) than the local brands (1x 101 to 4 x 101 per gm sample). Higher countsin the beef and chicken franchise burgers couldbe due to packaging and storage condition. Thelocal brand burgers were packed in small quan-tities i.e. 8 to 10 pieces per pack and storedfrozen. In the case of franchise burgers, largequantities were packed in a container, storedfrozen and sent to the outlets or restaurants.

Storing products in large quantities in contain-ers had lower penetration of cold air to theinternal part of the containers which takes alonger time to freeze. Babji et al. (1983) statedthat the time lapse between processing, han-dling, transportation, storage and packagingwould definitely increase chances of bacterialmultiplication.

The coliform and E.coli counts were low forall burger samples. However, some of the fran-chise beef and chicken burgers had highercounts for coliform, which were 17 (MPN)/gmsample for franchise beef burgers B and C, and27 (MPN)/gm sample for franchise chickenburger B. The Food Regulation of Malaysia(1985) stated that meat and meat product mustnot contained more than 50 Coliform countsper gram sample. Raw meat usually had highercoliform and E.coli counts, which ranged be-tween 10s to 104 (MPN)/100 gm in Indian beef(Babji and Seri Chempaka 1994) and between102 to 103 (MPN)/100 gm in chicken meat (SeriChempaka and Babji 1995). Low counts in theseburger samples indicated that inclusion of otheringredients and frozen storage conditions re-duced the number of bacteria and retardedtheir growth. Chuah and Yeoh (1984) statedthat E.coli is quite sensitive to low temperature,and freezing reduced the E. coli present. Thegrowth of mesophilic bacteria like E. coli is re-tarded at low temperatures, and no growth wasobserved below 5°C (Barnes 1976). Mandokhotand Garg (1985) informed that coliform indexhas found wide use in assessing the sanitaryquality of food including meats. Presence of E.

TABLE 6The colour values (Lrlightness, a-redness, b-yellowness) for local and franchise chicken burgers

Samples *

Local :AlDlElFlGlH I

Franchise :AB

L

62.75 ± 0.7672.48 ± 0.4763.83 ± 1.2143.78 ± 1.5468.61 ± 1.2065.35 ± 1.11

72.47 ± 0.7769.53 ± 0.47

Chicken

+5.17+2.40+5.62

+35.41+4.52+2.88

+2.03+5.55

Burgeri

± 0.35± 0.25±0.35± 0.76±0.28±0.35

±0.25±0.25

b

+17.13 ± 0.82+12.29 ± 0.41+13.73 ± 0.82+20.79 ± 0.58+16.96 ± 0.23+17.65 ± 0.26

+13.94 ± 0.39+14.13 ±0.41


PERTANIKA ). TROP. AGRIC. SCI. VOL. 23 NO. 2, 2000 109


TABLE 7Total plate count (TPC), coliform, E. coli (MPN/g sample) and S. aureus (CFU/g sample)

counts on local and franchise beef burgers.

Samples *

Local :AlBl

ClFlGlH I

Franchise :ABC

Total plate countCFU/g

3 x8 x

4 x1 X

3 x3 x

2 x2 x2 x

sample

10'10'

10'101

101

101

103

102

10*

Coliform count MPN/gsample (E.coli)

1(<1)1(<1)

2(<1)1(<1)3(<1)1(0)

1(0)17(0)

17«1)

S. aureus countCFU/g sample

1176263

-2


TABLE 8Total plate count (TPC), coliform, E. coli (MPN/g sample) and S. aureus (CFU/g sample)

counts on local and franchise chicken burgers

Samples *

Local :AlDlElFlGlHI

Franchise :AB

Total plate countCFU/g sample

4 x 101

3 x 10'1 x 101

3 x 101

4 x 10'3 x 101

2 x 10s

9 x 10*

Coliform count MPN/gsample (E.coli)

8 (<1)2 «1)0 (0)1 (0)

7 (<1)12 (<1)

1 (0)27 (<1)

S. aureus countCFU/g sample

13969622

-28


coli (enterococci) is employed as an indicator offaecal pollution in food.

S. aureus counts in most local brand beefand chicken burgers were varied and higherthan the franchise burgers which ranged berween2 to 11 CFU/ gm sample and 6 to 22 CFU/gramsample respectively. DHSS United Kingdom(1989) stated that S. aureus in food should notexceed 102 per sample respectively. Fennema,Powrie and Marth (1973) reported that althoughfreezing killed some microorganisms in food,many survived the freezing process and microor-ganisms that survived will grow and cause unde-sirable changes when the thawed food reaches a

suitable temperature. The processed meat prod-uct producers must be aware of the criticalcontrol points during processing and maintainlow temperature and clean sanitation duringmanual handling by the workers especially dur-ing processing, forming and packing the burg-ers. Most S. aureus biotype from human couldproduce enterotoxin (Brown 1982). S. aureus isa good hygienic indicator of meat base food andits presence is linked and heavy use of equip-ment and food handling (Shelton et al. 1962).In humans, the main reservoir for S. aureus isthe nose cavity and it spreads to the skin orwound directly or indirectly (Jay 1986).



The results obtained in the study showedthat there was no Salmonella sp present in allburger samples this meets the standards stipu-lated by the United Kingdom DHSS (1989) i.e.no Salmonella must be detected in 25 gram sam-ples. Low temperature at 5°C (Alcock 1987) orlower at 4.4°C (Nickerson and Ronsivalli, 1980)could retart the growth of Salmonella. Principalsources of Salmonella are dust, food handlers,pets, insects, rodents, birds, live-haul trucks andthe air. In the processing area, dust should beeliminated from the environment and equip-ment kept clean during the processing day.Clean-up procedures should include a sanitationprogramme aimed towards eliminating Salmo-nella, and should include spot bacterial checksprior to start up (Wabeck 1987). Microorgan-isms may pass from one raw food to another andfrom raw to cooked or processed foods by meansof equipment, cloths and surfaces and also viapeople handling raw and cooked food togetherwithout realising the fact and significance ofcontaminated raw materials. There is muchemphasis on the spread of infection from hu-man faecal excreters to foods but litde attentionhas been paid to the human hands passingSalmonella from one food to another (Hobbsand Gilbert 1970).

CONCLUSIONResults showed that there were some differencesin proximate and microbiology compositionbetween the local brand and the franchise burg-ers. Most franchise burgers had lower fat andcarbohydrate contents and higher protein andmoisture contents compared to the local brands.High fat and carbohydrate contents and lowprotein and meat contents in the local brandburgera showed the utilization of carbohydratefillers/binders and addition of fat. Thus affectedthe colour of the product. In some local brandsand franchise burgers, the utilization of non-meat protein ingredients and addition of highamount of water may have occured based theanalysis of which showed high protein and mois-ture contents but low in fat, carbohydrate andmeat contents. Absence of Salmonella sp, lowTotal Plate Count (TPC), Coliform, R coli and S.aureus counts in the burger samples showed thatthe manufacturers had paid due attention toquality especially in microbiology compositionby maintaining the sanitation and cleanliness ofthe equipment, storage facilities and workers in

the processing plant. Such a study should becarried out from time to time to monitor thequality of the products in terms of nutritionalvalue and microbiological safety.

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Received: 19 September 1998Accepted: 20 June 2000


Subject Index for Volume 23 Nos. 1 and 2, September 2000

Aba 67-68, 70-72Abscisic acid see AbaAcacia auriculformis 97-100Acacia crassicarpa 97-98, 100Acacia mangium 97-100Animal feeding 37-40Antidiabetic 29

Bioherbicide 83Body measurements 55-58Body weight 55-58Broilers see Broiler chickensBroiler chickens 37-40Burger 103-111

Capsicum annuum 67-68, 83-87Carica papaya 15-16Chemicophysical properties 1-2, 12Clingwrap 1, 3-12Crop losses 83Crop residues 89-94Crops 75-77, 80Cycling 89-90, 94Cyperus rotundus 83, 87

Dactylaria higginsii 83-88Diabetes mellitus see DiabetesDiabetes 29-33Diet 37-39Drought stress 67, 69, 70-71Drug plants 29, 33Dust 61-62

Ecological zone 75, 78-80

Fertility 29-30Food colourants 103-105, 108Forced vital capacity 61Franchise 103-111

Growing period see Growth periodGrowth 55-57Growth period 75Guavas 15-20

Hypoglycaemia 29-31, 33

Interference 83-84

Keeping quality 1, 3KMnO4 see Potassium permanganate

Landagricultural 2-6ex-mining 1-6

LDPE see Polyethylene low densityLepidoptera 97-98Lungs 61-65

Macronutrients see NutrientsMaize 37-40, 75-80Males 29-33Mangifera indica 2-6Mangoes 2-6Meat content 103, 107-108, 111Medicinal properties 29Medicinal plants see Drug plantsMicrobiology 103-104, 111Musa cavendishii see Musa paradisiacaMusa (Bananas) 1-12Musa paradisiaca 1-12Myoglobin 103-105, 108-109

Niacin see NicotinamideNicotinamide 37-40Noctuidae 97Nutrients 89Nutritional requirements 37-40

OGTT see Oral Glucose Tolerance TestOpen system erosion plots 43-51Oral Glucose Tolerance Test 29, 31

Palm kernels 37-38Papayas 15-20Paraffin 1, 4-12Paraserianthes falcataria 97-98, 100Pathogenicity 23Peat soils 89, 91, 94Peninsular Malaysia 23Pineapples 89-91Piper nigrum 67-71, 83-88Physical characteristics 55-57Physicochemical properties see Chemicophysical

propertiesPhysiological functions 61-65Plantago major 29-30, 33Planting window 75-78, 80Polyethylene

low density 1-12Postharvest control 1-12Postharvest treatment see Postharvest controlPotassium permanganate 1, 4-12


Subject Index for Volume 23 Nos. 1 and 2, September 2000

Proximate composition 103-106, 111Psidium guajava 15-16Purple nutsedge 83-87

Rainfall parameters 43Requirements, feed see Nutritional

requirementsRespiratory diseases 61-65Runoff 43, 47-48, 50-51

Sambar deer 55, 58Seedlings 67Simulation models 75Soil characteristics 43Sperm count 29, 32-33Spices 61-65Spirama retorta 97-100SPltNPV see Spodoptera litura,

nucleopolyhedrovirusSpodoptera litura, nucleopolyhedrovirus

23-27

Stomal conductance see stomata andtranspiration

Stomata 67-72Storage life see Keeping qualitySurface wash 43-51

Trace elements contamination 15-16Transpiration 67-72

Virus characteristics 23-27Vital capacity 61

Waste management 89-94Water plant relations 67Water relations, plant see Water plant relationsWater stress see Drought stressWaxing 2Weeds 83, 84

Yield losses 83


Author Index for Volume 23 Nos. 1 and 2, 2000

A. R. Anuar see Anuar Abdul RahimAbd. Karim Abd. Samad 97-101Abd. Razak, H. 75-81Ahmad Husni Mohd Hanif 89-95Ahmad Said Sajap 23-28, 97-101Ahmed, O. H. 89-95Aminuddin, B. Y. 75-81Ang, L. H. 15-22Anuar Abdul Rahiin 89-95Azizah Osman 1-14

Babji, A. S. 103-112Bewick, T. A 83-88

Charudattan, R. 83-88Chee, B. J. 29-35

Davies, W. J. 67-73Dawendjiwan 55-59

Faridah Mohamad 61-66

Kadir, B. 83-88Kueh, B. L. 29-35

H. Noor see Hamdan Mohd NoorHamdan Noor see Hamdan Mohd NoorHamdan Mohd Noor 29-35, 61-66Hussain A Kadir 23-28

Ismail Idris 55-59

Juing, M. 29-35

Kotulai, James R. 23-28]

Lau W. Hong 23-28

M. H. A. Husni see Ahmad Husni Mohd HanifM. M. Hanafi see Mohd Hanafi MusaMohamad A. Bakir 23-28Mohd Hanafi Musa 89-95Mohd Fauzi, R. 75-81Mohd Razi Ismail 67-73

Ng, L. T. 15-22Norani A Samad 23-28Nuri, M. N. 103-112

Oloyo, R. A. 37-41

Razali Mustaffa 1-14

Sabry Al-Toum 43-53Saidi Moin 55-59Salmah Yusof 1-14Samto Sulah 55-59Seri Chempaka, M. Y. 103-112Sharifah Mastura S. A. 43-53Stall, W. M. 83-88Suhaila Mohamed 1-14Suherman,J. 103-112

Syed Omar, S. R. 89-95

Wahidah Sansi 61-66

Zolkepli Othman 29-35, 61-66


Acknowledgements

The Editorial Board acknowledges the assistance of the following reviewers in the preparation ofVolume 23, No. 1 8c 2 of this journal

Dr. Abdul Razak AlimonAhmad Abdul RahmanDr. Anuar Abd. RahimDr. HenrickJ. AndersonDr. Baharudin KasranDr. Che Fauziah IshakProf. Dr. Dahlan IsmailDr. Faizah Abood HarrisDr. M.L GreaserDr. Idris Abdol GhaniDr. Ismail AhmadDr. Jamal TalibAssoc. Prof. Dr. Lai Food SeeDr. Leslie C. Lewis

Prof. Dr. Mak Joon WahDr. Mohd. Fauzi RamlanProf. Dr. Mohd. Khanif YusofDr. Radziah OthmanAssoc. Prof Ramlah HamidAssoc. Prof. Dr. Ridzuwan Abd. HalimDr. Russly A. RahmanProf. Dr. Sariah MeonDr. SivarajasingamProf. Dr. Suhaila MohamedProf. Dr. Tien MuchtadiDr. Wendy FornoAssoc. Prof. Dr. Zailina Hashim


Preparation of Manuscript

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Typing and PaperManuscripts should be typewritten on A4 paper, doublespaced, and of letter quality with 4cm margins on allsides.

Title pageThis page should bear the title of the paper with thefull name of the author(s), followed immediately bythe address. Author citation should also be provided.A short title not exceeding 60 characters should beprovided for the running headline.

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In case of citing an author(s) who has publishedmore than one paper in the same year, the papersshould be distinguished bv addition of a small letter,e.g. Choa (1979a); Choa (1979b); Choa (1979c).

References should be arranged alphabeticallyaccording to first author. Serial titles are to be givenin full.

Examples of reference citations are provided;

MonographsTurner, H.N. and S.S.Y. Yong. 1969. QuantitativeGenetics in Sheep Breeding. Ithaca: Cornell UniversityPress.

SerialsHo, Y.W. and A. Nawawi. 1991. Effect of carbon andnitrogen sources on growth of Ganodetma boninensefrom oil palm. Journal of Plant Protection in the Tropics 8:37-43

Chapter in Edited BookRoberts, D.W. 1980. Toxins of entomopathogenicfungi. In Microbial Control of Pests and Plant Diseases, ed.H.D. Burgess, p. 441-463. New York: Academic Press.

ProceedingsHussein, M.Y. 1986. Biological control of aphids onpotatoes by inundative releases of predators. InBiological Control in the Tropics, ed. M.Y. Hussein andA.G. Ibrahim, p. 137-147. Serdang: Universiti PertanianMalaysia Press.

Unpublished Materials (e.g. theses, reports 8cdocuments)Normah, M.N. 1987. Effects of temperature on rubber{Hevea brasiliensis Muell - Arg.) Seed storage. Ph.D.Thesis, 206p. Universiti Pertanian Malaysia.

The abbreviation for Pertanika Journal of TropicalAgricultural Science is Pertanika]. Trop. Agric Sci.


Volume 23 Number 2 (September) 2000

Contents

Effect of Spice Dust an Lung Functions and Respiratory Symptoms in 61

Spice Factory Workers in Selangor - Hamdan Noor, Wahidah Sansi,

Zolkepli Othman and Fandah Mohamad

Leaf Growth and Stomatal Sensitivity after Water Stress Relief and its 67

Relation to Xylem Sap Absicisic Acid - Mohd liazi Ismail mid W.JDavies

CEREZ-Maize Simulation Model: Establishment of Planting Windows for 75

Grains Maize under Rainfed Conditions - H. Abd. Razak, B. Y. Aminuddin

and R. Mohd Fauzi

Effect of Dactylana higginsii on Purple Nut sedge (Cyperus rotundus)

Interference with Pepper (Capsium annuumh) - B. Kadir, R Charudattan,

W.M Stall and T. A. Bewick

83

Macronutrients Distribution and Cycling of Pineapple Planted on Tropical

Peat - O.H. Ahmed. M.H.A. Husnu M.M. Hanafi, S.R Syed Omar

A.R. Anuar

89

Effects of Food Plants on Development of Spirama Retorta (Lepidorptera: 97

Noctuidae) - Ahmad. Said Sajap and Abd. Karim Abd. Sam ad

Quality Assessment of Local and Franchise Beef and Chicken Burgers - 103

A.S. Babji M.N. Nuri, J, Suherman and M.Y, Sen Oiernpaka

ISSN 1511-37Q109

i i i tropica ii i ixl - pertanika journal papers/jtas vol... · issn: 1511-3701 tropica i v*» i i...

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