research article improving lowland rice ( o. sativa l. cv

Research ArticleImproving Lowland Rice (O sativa L cv MR219) PlantGrowth Variables Nutrients Uptake and Nutrients RecoveryUsing Crude Humic Substances

Perumal Palanivell1 Osumanu Haruna Ahmed123 Nik Muhamad Ab Majid3

Mohamadu Boyie Jalloh4 and Kasim Susilawati1

1Department of Crop Science Faculty of Agriculture and Food Sciences Universiti Putra Malaysia Bintulu Sarawak Campus97008 Bintulu Sarawak Malaysia2Agriculture and Environment Borneo Eco-Science Research Center Faculty of Agriculture and Food SciencesUniversiti Putra Malaysia Bintulu Sarawak Campus 97008 Bintulu Sarawak Malaysia3Institute of Tropical Forestry and Forest Products (INTROP) Universiti Putra Malaysia 43400 Serdang Selangor Malaysia4Faculty of Sustainable Agriculture Universiti Malaysia Sabah Kampus Sandakan Locked Bag No 390509 Sandakan Sabah Malaysia

Correspondence should be addressed to Osumanu Haruna Ahmed osman60hotmailcom

Received 6 February 2015 Accepted 3 April 2015

Academic Editor Antonio Ferrante

Copyright copy 2015 Perumal Palanivell et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

High cation exchange capacity and organic matter content of crude humic substances from compost could be exploited to reduceammonia loss from urea and to as well improve rice growth and soil chemical properties for efficient nutrients utilization inlowland rice cultivation Close-dynamic air flow system was used to determine the effects of crude humic substances on ammoniavolatilization A pot experiment was conducted to determine the effects of crude humic substances on rice plant growth nutrientsuptake nutrients recovery and soil chemical properties using an acid soil mixed with three rates of crude humic substances (20 40and 60 g potminus1) Standard procedures were used to evaluate rice plant dry matter production nutrients uptake nutrients recoveryand soil chemical properties Application of crude humic substances increased ammonia volatilization However the lowest rate ofcrude humic substances (20 g potminus1) significantly improved total dry matter nutrients uptake nutrients recovery and soil nutrientsavailability compared with crude humic substances (40 and 60 g potminus1) and the normal fertilization Apart from improving growthof rice plants crude humic substances can be used to ameliorate acid soils in rice cultivation The findings of this study are beingvalidated in our ongoing field trials

1 Introduction

Ultisols and Oxisols are the most common agricultural soilsin the tropics Besides being highly weathered these soilsare acidic very low in cation exchange capacity (CEC) andinherently low in nutrients [1] The large amounts of oxidesand hydroxides of Fe andAl inUltisols andOxisols have beenassociated with the abundance of variable charge colloidslow pH and low CEC [2 3] These oxides and hydroxidescommonly fix large amounts of soluble phosphate leading tolow concentrations of available Phosphorus (P) in soil solu-tion [4 5] Furthermore in lowland rice fields (waterlogged

condition) urea is mostly lost through NH3

volatilizationAmmonia volatilization is higher in waterlogged conditioncompared to nonwaterlogged condition [6 7] and this NH

3

volatilization occurs when urea is hydrolyzed to ammoniumcarbonate (equation (1)) Subsequently ammonium carbon-ate decomposes into CO

2

H2

O and NH3

(equations (2) and(3)) [8]

Urea Hydrolysis

(NH2

)2

CO + 2H2

O Soil urease997888997888997888997888997888997888997888rarr (NH

4

)2

CO3

(1)

Hindawi Publishing Corporatione Scientific World JournalVolume 2015 Article ID 906094 14 pageshttpdxdoiorg1011552015906094

2 The Scientific World Journal

(NH4

)2

CO3

+ 2H+ 997888rarr 2NH+4

+ CO2

+H2

O (2)

NH+4

+OHminus 999445999468 NH3

+H2

O (see [8]) (3)

Thus the aforementioned problems lead to nutrients unavail-ability for rice plant growth and development To overcomethe stated problems farmers apply fertilizers excessively toattain higher yield However unbalanced use of N and Pfertilizers causes environmental problems such as eutroph-ication groundwater pollution acid rain deposition soilacidification and greenhouse gas emissions [9ndash12]

Utilization of humic substances in acidic soils wasreported not only to have reduced Al3+ and Fe2+ but also tohave increased P [13] Reduction of Al3+ and Fe2+ ions in soilsolution is essential as this prevents P from being precipitatedas strengite vivianite variscite and various minerals of theplumbogummite group [14]Moreover P fixation in acid soilscan be reduced by increasing soil pH as availability of P varieswith variation in soil pH For example most of P is availablefor plant uptake at neutral pH [8] This suggests that thesawdust ash used to extract crude humic substances in thisstudy can be exploited to increase pHof acidic soils because oftheir basic nature (pH 11) Crude humic substances which areproduced from rice straw compost and sawdust ash can alsobe used to improve soil chemical properties because theseorganic substances can increase soil pH and organic matter[15] Additionally the high CEC of rice straw compost canbe exploited to improve CEC of acid soils and to as wellretain cations such as NH

4

+ K+ Ca2+ andMg2+ In additiongood retention of cations including NH

4

+ ion ammoniavolatilization from urea and nutrients leaching could be sig-nificantly reduced Ammonia volatilization from urea as anexample can be reduced with application of materials whichare high in CEC [16ndash18] Humic substances which are highin CEC have been used to control ammonia volatilizationin nonwaterlogged condition In nonwaterlogged conditionshumic acids and fulvic acids from tropical peat coal palmoil mill effluent sludge and crude humins from composts[19ndash23] have been used to reduce NH

3

loss from urea Inwaterlogged soils Clinoptilolite zeolite has been used toreduce ammonia volatilization [17 18 24]

Apart from fewer studies which had been carried out todetermine the effects of humic substances on ammonia lossand soil chemical properties of waterlogged soil isolation(extraction fractionation and purification) of humic acidsfulvic acids and humins is laborious and expensive Hencein this present study rice straw compost was rather mixedwith sawdust ash to produce crude humic substances Wehypothesized that the application of crude humic substanceswhich are high in CEC could reduce NH

3

volatilization fromurea increase rice plant growth nutrients uptake recoveryand aswell improving soil chemical properties inwaterloggedcondition Thus this study was conducted to determine theeffects of mixing an acid soil (Typic Paleudults) with crudehumic substances at three rates (20 40 and 60 g potminus1) inwaterlogged condition on NH

3

volatilization from urea riceplant growth nutrients uptake and recovery and improve soilchemical properties

Table 1 Selected chemical properties of Typic Paleudults (BekenuSeries) soil before incubation and pot study

Property Currentstudy

Standard datarange

(0ndash36 cm)pHwater 441 46ndash49

Bulk density (g cmminus3) 116 NA

TOC () 143 057ndash251

Total N () 008 004ndash017

Exchangeable NH4

+ (mg kgminus1) 2102 NA

Available NO3

minus (mg kgminus1) 701 NA

Available P (mg kgminus1) 485 NA(Cmol (+) kgminus1)

CEC 1197 386ndash846Exchangeable K+ 010 005ndash019Exchangeable Ca2+ 025 NAExchangeable Mg2+ 034 NAExchangeable Na+ 022 NAExchangeable Fe2+ 019 NAExchangeable Cu2+ Trace NAExchangeable Zn2+ 001 NAExchangeable Mn2+ 002 NATotal titratable acidity 086 NAExchangeable H+ 064 NAExchangeable Al3+ 022 NANA not available Paramanathan [34]

2 Materials and Methods

21 Soil Sampling Preparation and Characterization TypicPaleudults (Bekenu Series) soil was sampled at 0 to 25 cmin an uncultivated area of Universiti Putra Malaysia BintuluSarawak Campus Malaysia (latitude 3∘121015840N and longitude113∘41015840E) The soil was air-dried ground and sieved to pass toa 5mm sieve The soil was analyzed before and after the potstudy for pH in distilled water (at ratio of 1 25 soil water)using a digital pH meter [25] total carbon using loss-on-ignition method [26] total organic carbon (TOC) andorganic matter (OM) content using Walkley-Black method[27] cation exchange capacity (CEC) using the ammo-nium acetate leaching method [28] total N using Kjeldahlmethod [29] and available NO

3

minus and exchangeable NH4

+

[30] Exchangeable cations and available P were extractedusing the Double Acid Method [31] after which cationswere determined using Atomic Absorption Spectrometer(AAnalyst 800 Perkin Elmer Instruments Norwalk CT)whereas available P was determined using the Blue Method[32] Total titratable acidity was determined using acid-basetitration method [33] The selected chemical and physicalproperties of the soil (Table 1) used in this study are typicalof Typic Paleudults (Bekenu series) and they are consistentwith those reported by Paramananthan [34] except for CECexchangeable calcium and magnesium

The Scientific World Journal 3

22 Rice Straw Compost and Sawdust Ash Production Thecompost used in this study is produced from mixture ofrice straw (75) + chicken dung (15) + molasses (6) +urea (2) + rock phosphate (2) [35] Sawdust dust wasincinerated at 600∘C using muffle furnace for 10 hours in analuminium ware (size 30 cm length times 17 cm width times 8 cmheight) until almost white ash is produced

23 Rice Straw Compost and Sawdust Ash CharacterizationThe rice straw compost and sawdust ash were analyzed forpH in distilled water (at ratio of 1 10 compost water 1 100ash water) using a digital pH meter [25] total N usingKjedahl method [29] CEC using the ammonium acetateleaching method [28] organic matter and total organiccarbon content using loss-on ignition method [36] Total Pand cation contents in the rice straw compost and sawdustash were extracted using the single dry ashing method [28]Phosphorus in the extract was quantified using the BlueMethod [32] whereas cations content were determined usingatomic absorption spectrophotometer (AAnalyst 800 PerkinElmer Instruments Norwalk CT) The molarity of sawdustash (at ratio of 1 100 ash water) was determined using acid-base titration [37] with modification of 180 rpm instead of150 rpmHumic acids and crude humins content in rice strawcompost were determined using method of Ahmed et al [38]and Palanivell et al [35 39] Total organic carbon organicmatter content humic acids and CEC of the rice strawcompost and pH and total calcium content of the sawdust ashwere higher as expected (Table 2)

24 Treatments Evaluation for Ammonia Loss from UreaThe ammonia loss incubation study was conducted usingclose-dynamic air flow system [40 41] Treatments werearranged in a Completely Randomized Design (CRD) withthree replications The treatments per 250 g of soil evaluatedin 500mL conical flask were as follows

(i) C1 soil alone(ii) C2 soil + complete fertilization(iii) CHS1 soil + complete fertilization + 20 g rice straw

compost + 2 g sawdust ash(iv) CHS2 soil + complete fertilization + 40 g rice straw

compost + 4 g sawdust ash(v) CHS3 soil + complete fertilization + 60 g rice straw

compost + 6 g sawdust ash

The complete fertilization is equivalent to 131 g urea + 139 gERP + 088 g MOP + 016 g Kieserite + 053 g chelated ZnCo-Bor per experimental unit The amounts of fertilizers usedwere scaled down for plant density of 3 rice plants hillminus1 Thisfertilizer rate (151 kg haminus1 N 978 kg haminus1 P

2

O5

130 kg haminus1K2

O and 76 kg haminus1 MgO) was based on the recommendedfertilizer for rice byMudaAgricultural Development Author-ityMalaysia [42] with additional micronutrients (23 kg haminus1B 4 kg haminus1 Cu and 4 kg haminus1 Zn) [43] The amounts of ricestraw compost used in this study were deduced from theliterature [44ndash49] where 5 10 and 15 tons haminus1 equivalent to20 40 and 60 g potminus1 were used

Table 2 Selected chemical properties of rice straw compost andsawdust ash

Property Rice strawcompost

Sawdustash

pH 758 1103CEC (Cmol (+) kgminus1) 9360 ndMolarity (w v = 1 100) (M) nd 0002

()Organic matter 7400 ndTotal organic carbon 4292 ndHumic acids 1097 ndCrude humins 8793 ndTotal N 185 ndTotal P 075 047Total K 242 027Total Ca 120 763Total Mg 075 109Total Na 024 004Total Fe 025 357Total Zn (mg kgminus1) 164 683Total Mn (mg kgminus1) 223 1833Total Cu (mg kgminus1) 71 213

The incubation study was carried out by mixing soil withrice straw compost and sawdust ash for the treatments withcrude humic substances alone after which the mixture wasmoistened to 100 of field capacity and left overnight toequilibrate Before the fertilizers were applied the water levelin each conical flask was maintained at 3 cm from the soilsurface to ensure that the system was waterlogged The waterlevel was marked on the conical flasks The water level in theconical flask was maintained throughout incubation period(33 days) by adding distilled water as the deficit of the originalwater level The fertilizers were applied on the soil surfaceand air was passed through the volatilization system at arate of 25 Lminminus1 and volatilized ammonia from urea wascaptured in 75mL of 2 boric acid solutionwith bromocresolgreen and methyl red indicator The rate of air flow wasmeasured using a Gilmont flow meter (Gilmont InstrumentGreat Neck NY USA) The boric acid solution was replacedevery 24 h and back titrated with 005M HCl to determineammonia loss from urea This measurement was continueduntil the ammonia loss decreased to 1 of the N added in thesystem [24 40]

25 Germination Media Selection Before the pot study ger-mination media selection was done using rice seeds varietyof MR219 (commonly used rice seed in Malaysia) This studywas carried out using plastic waremeasuring 17 cm (length)times12 cm (width) times 65 cm (height) filled with 100 g of germina-tion media and the media were moistened up to 100 of itsfield capacity The river sand used in this study was washedwith tap water after which it was washed thoroughly withdistilled water until the pH of the sand was neutral (pH 7)


0

1

2

3

4

5

6

0 5 10 15 20 25 30

Dai

ly am

mon

ia lo

ss

( o

f app

lied

N)

Incubation period (days)

C1C2CHS1

CHS2CHS3

Figure 1 Daily ammonia loss for different treatments (C1 soil aloneC2 soil + complete fertilization CHS1 soil + complete fertilization+ 20 g rice straw compost + 2 g sawdust ash CHS2 soil + completefertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3soil + complete fertilization + 60 g rice straw compost + 6 g sawdustash) over 33 days of incubation

c

ba a a

020406080

C1 C2 CHS1 CHS2 CHS3Treatment

Tota

l NH

3lo

ss (

)

Figure 2 Total ammonia loss for different treatments (C1 soil aloneC2 soil + complete fertilization CHS1 soil + complete fertilization+ 20 g rice straw compost + 2 g sawdust ash CHS2 soil + completefertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3soil + complete fertilization + 60 g rice straw compost + 6 g sawdustash) at 33 days of incubation Different alphabets indicate significantdifference between means using Tukeyrsquos test at 119875 le 005 The errorbars are the plusmn standard error of triplicates

Ten rice seedswere seeded on each germinationmediumTheexperimental design was Completely Randomized Design(CRD) with 3 replications The treatments evaluated were asfollows

(i) G1 100 sand

(ii) G2 5 rice straw compost + 95 sand

(iii) G3 10 rice straw compost + 90 sand

(iv) G4 15 rice straw compost + 85 sand

After 7 days of seeding germination rate root elongationand shoot elongation were measured using a digital verniercaliperwhereas relative seed germination germination indexrelative root elongation and relative shoot elongation ofrice seedling were determined as described by Araujo andMonteiro [50] The ammonia volatilization and germinationmedium selection studies were conducted in a laboratoryat the Research Center of Universiti Putra Malaysia Bintulu

Table 3 Fertilization schedule for the pot study

Days afterseeding (DAS)

Urea ERP MOP Kieserite Zncobor(g potminus1)

15 DAS 055 079 024 mdash mdash35 DAS 040 mdash 024 006 05350 and 70 DAS 018 030 020 005 mdash

Sarawak Campus Malaysia which had an average temper-ature of 296∘C (range 268ndash319∘C) and an average relativehumidity of 710 (range 501ndash851)

26 Pot Study The quantity of the soil used in the pot studywas calculated based on the soilrsquos bulk density A 1 kg of air-dried soil was filled in a potmeasuring 125 cm (top diameter)times 10 cm (bottom diameter) times 9 cm (height) Before plantingrice seeds variety of MR219 were germinated in a plasticware filled with germination medium (100 sand) whichwas selected from the germination medium selection studyThe treatments evaluated in this pot study were the sameas those used in the ammonia volatilization study Howeverfertilization was done as summarized in Table 3

The pots were filledwith soil only in C1 andC2 For CHS1CHS2 and CHS3 soil was mixed thoroughly with differentrates of crude humic substances (20 40 and 60 g potminus1)according to the treatments Crude humic substances wereprepared by mixing sawdust ash rice straw compost andwater thoroughly (at ratio of 1 10 100) and left for 24 h beforemixing with soil Potting was done 24 h before transplantingThe water level in each pot was maintained at 2 cm fromthe soil surface At 7 days after seeding rice seedlings weretransferred into pots (planting density of 3 seedlings per potwhich is equivalent to 3 seedlings hillminus1) [51] This pot trialwas carried out in a rain shelter at Universiti Putra MalaysiaBintulu Sarawak Campus Malaysia and the treatments werearranged in Completely Randomized Design (CRD) with 4replications The experimental area has total precipitation of753mm average relative humidity of 85 (range 70ndash95)and mean minimum and maximum temperatures of 233∘Cand 327∘C respectively throughout the study period [52]

Plant height number of tillers and number of leaveswere recorded at harvest (90 days after seeding) The riceplants were harvested and partitioned into abovegroundbiomass and root before heading stage (end of vegetativestage) This was due to the insufficient amount of soil tosupport rice plant up to reproduction stage Besides it is noteconomically practical to estimate yield of rice based on potexperiment The plant parts were oven-dried at 60∘C until aconstant weight obtainedThe oven-dried plant samples wereground using Retsch SM100 comfort cutting mill (RetschGmbH Germany) after which they were analyzed for totalN [29] and crude silica [53] The plant samples were digestedusing the single dry ashing method [28] after which K CaMg Cu Zn Fe and Mn contents were determined usingatomic absorption spectrophotometer (AAnalyst 800 PerkinElmer Instruments Norwalk CT) whereas P was determinedusing Molybdenum Blue Method [32] Nutrient uptake was


a a a a

0

20

40

60

80

100

120

G1 G2 G3 G4

Ger

min

atio

n ra

te (

)

Treatment

a

b b b

0

20

40

60

80

100

G1 G2 G3 G4

Shoo

t elo

ngat

ion

(mm

)

Treatment

a a a

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120

Relat

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erm

inat

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()

G2 G3 G4Treatment

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elon

gatio

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m)

G1 G2 G3 G4Treatment

a

aa

00

10

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G2 G3 G4

Relat

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oot e

long

atio

n (

)

Treatment

a

a

a

00

10

20

30

40

G2 G3 G4

Ger

min

atio

n in

dex

()

Treatment

aa a

0

5

10

15

20

25

30

G2 G3 G4

Relat

ive s

hoot

elon

gatio

n (

)

Treatment

Figure 3 Treatments (G1 100 sand G2 5 rice straw compost + 95 sand G3 10 rice straw compost + 80 sand and G4 15 rice strawcompost + 85 sand) effect on rice seeds germination rate shoot elongation root elongation relative germination relative shoot elongationrelative root elongation and germination index of rice seedlings at 7 days after seeding Different alphabets indicate significant differencebetween means using Tukeyrsquos test at 119875 le 005 The error bars are the plusmn standard error of triplicates


b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100

C1 C2 CHS1 CHS2 CHS3

Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1

Figure 4 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on plant height number of leaves tillers and dry matter production of rice plant at 90 days afterseeding Different alphabets indicate significant difference between means using Tukeyrsquos test at 119875 le 005 The error bars are the plusmn standarderror of quadruplicates

calculated by multiplying nutrient content with plant dryweight Rice plant nutrient recovery was calculated using themethod of Dobermann [54]

27 Statistical Analysis Analysis of variance (ANOVA) wasused to detect significant differences among treatmentswhereas Tukeyrsquos test was used to compare treatment meansusing Statistical Analysis System version 92 [55]

3 Results and Discussion

Ammonia volatilization was observed for soil with completefertilization without crude humic substances (C2) and soilwith crude humic substances (CHS1 CHS2 and CHS3) onthe first day of incubation (Figure 1) Ammonia loss fromC2 CHS1 CHS2 and CHS3 lasted for 32 days Ammoniavolatilization decreased at 6 11 18 and 24 days of incubationand increased at 7 12 19 and 25 days of incubation in allthe treatments except for C1 The fluctuation in ammoniavolatilization during the incubation study was due to thereaction between urea and soil water to form NH

4

+ [24 56]As the soil surface rapidly dried due to air velocity in thechamber NH

3

from urea decreased at 6 11 18 and 24 daysof incubation Ammonia loss decreased when soil water wasinsufficient for the chemical reaction and it increased at 7 12

19 and 25 days of incubation upon addition of water Thisobservation is consistent with that of Bundan et al [56] andPalanivell et al [24] No ammonia volatilization in soil alone(C1) suggests that soil alone did not contribute to ammonialoss This observation is consistent with findings reported inprevious studies [41 56]

Treatments with crude humic substances (CHS1 CHS2and CHS3) showed higher NH

3

loss compared to the normalfertilization (C2) (Figure 2) The basic nature of the sawdustash (pH 1103) used in this study might have contributed tothe NH

3

volatilization in the treatments with crude humicsubstances (CHS1 CHS2 and CHS3) This is because rapidconversion of NH

4

+ ions to NH3

gas during urea hydrolysisoccurs at higher pH [57 58] However in a related studyapplication of crude humins from composts in nonwater-logged condition showed no effect on NH

3

volatilizationcompared with normal fertilization [23]

The effects of all the treatments on seed germinationrate relative germination relative shoot elongation relativeroot elongation and germination index were statisticallysimilar (Figure 3) Application of rice straw compost (G2 G3and G4) showed no significant effects on seed germinationrate and relative germination However rice straw compost(G2 G3 and G4) significantly reduced root elongation andshoot elongation compared with sand alone (G1) (Figure 3)Gallardo-Lara and Nogales [59] demonstrated that high N


cc

ab


c

ba

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0

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ba

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b

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a b

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a b

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a a

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b b

a a

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dc

a

b

c

b

a

b

0000

0010

0020

0030

0040

C1C1 C2 CHS1 CHS2 CHS3Treatment

C2 CHS1 CHS2 CHS3Treatment

c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)

Figure 5 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on N P K crude silica Ca Mg Na Cu Zn Mn and Fe uptake of rice plant at 90 days afterseeding Different alphabets indicate significant difference between means using Tukeyrsquos test at 119875 le 005 The error bars are the plusmn standarderror of quadruplicates


b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)

Figure 6 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on rice plant N P K Mg Cu and Zn recovery at 90 days after seeding Different alphabetsindicate significant difference between means using Tukeyrsquos test at 119875 le 005 The error bars are the plusmn standard error of quadruplicates

content in compost and compost rate can cause an inhibitoryeffect on seed germination and growth Thus this germina-tion media test shows that the use of rice straw compost asa germination medium for rice seeds is not suitable This isfurther supported by the lower germination index (less than80) of the rice seeds on G2 G3 and G4 [50] In a relatedstudy rice straw was transformed into soil-like substratethrough aerobic fermentation and bioconversion using fungiand worms before using the product as a planting medium[60] Hence sand alone (G1) was used as germinationmedium for the rice seedlings production in our pot study

CHS1 and CHS2 significantly improved rice plant heightdry matter production number of leaves and tillers com-pared with normal fertilization (C2) (Figure 4) The lowestcrude humic substances rate (CHS1) showed the highestdry matter production compared with other treatmentsAccording to Smith and Dilday [61] high nutrients uptake(especially N and silica) increased rice plant growth and drymatter production and this observation is consistent with theeffect of CHS1 as this treatment showed the highest nutrientuptake (N crude Si CaMg Zn Cu and Fe) and recovery (N

Mg Zn and Cu) compared with other treatments (Figures5 and 6) The rice plants under the highest crude humicsubstances rate (CHS3) died (Figures 4 5 and 6) The highsoil pH (pH 713) of CHS3 could be the reason for the riceplant death because the rice plant variety of MR219 growswell within soil pH of 55 to 65 [42]

The treatments with crude humic substances (CHS1 andCHS2) showed higher nutrients uptake (K P crude Si CaMg Na Mn and Zn) and recovery (P K and Mg) (Figures5 and 6) compared with normal fertilization (C2) The riceplants with higher crude humic substances (CHS2) showedthe highest P uptake and recovery compared with othertreatments (Figures 5 and 6) whereas the lowest crude humicsubstances rate (CHS1) showed the highest uptake ofN crudeSi Ca Mg Zn Cu and Fe and recovery of N Mg Zn andCu compared with other treatments (Figures 5 and 6) Thehighest nutrient uptake and recovery in CHS1 was because ofthe highest dry matter production in CHS1 (Figure 4)

The treatments with the different rates of crude humicsubstances (CHS1 CHS2 and CHS3) significantly increasedsoil pH compared with C1 (soil alone) and C2 (normal


de

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ater

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labl

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g kgminus

1)

a

b b b b000

005

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030


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ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

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0300

0350


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ange

able

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(Cm

ol (+

) kgminus

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c cc

00

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Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)

Figure 7 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on soil pH total titratable acidity exchangeable H+ exchangeable Al3+ and available P contentat 90 days after seeding Different alphabets indicate significant difference between means using Tukeyrsquos test at 119875 le 005 The error bars arethe plusmn standard error of quadruplicates

fertilization) (Figure 7) Soil pH also increased with increas-ing rate of crude humic substances (CHS1 lt CHS2 lt CHS3)(Figure 7) due to the high pH and basic cations of thesawdust ash used in this study (Table 2) Soil total titratableacidity and exchangeable H+ were significantly lower in thecrude humic substances treatments (CHS1 CHS2 andCHS3)compared with soil alone (C1) and normal fertilization (C2)

(Figure 7) The high pH and basic cations of the sawdustash (Table 2) in CHS1 CHS2 and CHS3 might have reducedsoil titratable acidity and exchangeable H+ Soil alone treat-ment (C1) showed the highest total titratable acidity andexchangeable Al3+ compared with other treatments becausesome of the P fertilizer (ERP) in C2 CHS1 CHS2 and CHS3might have reduced exchangeable Al3+ and total titratable


d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)

Figure 8 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on soil total carbon total organic carbon organic matter cation exchange capacity exchangeableNH4

+ available NO3

minus and total nitrogen content at 90 days after seeding Different alphabets indicate significant difference between meansusing Tukeyrsquos test at 119875 le 005 The error bars are the plusmn standard error of quadruplicates

acidity compared with soil alone (C1) as in acidic soilshydroxides and oxides of Al3+ are precipitated by H2PO4

minus

as variscite and various minerals of the plumbogummitegroup [14] Available P in normal fertilization and crudehumic substances (CHS1 CHS2 and CHS3) were statisticallysimilar (Figure 7) However the highest rate of crude humicsubstances (CHS3) showed higher available P compared withCHS2 The lower available P in CHS2 compared with CHS3was due to the higher P uptake and recovery by rice plantsunder CHS2 as those under CHS3 died

CHS1 CHS2 and CHS3 increased soil organic matter(OM) total organic carbon (TOC) total carbon (TC) andcation exchange capacity (CEC) compared with soil alone

(C1) and normal fertilization (C2) (Figure 8) Higher OMTOC TC and CEC of the crude humic substances appliedsoil (CHS1 CHS2 and CHS3) were because of the inherentcontents of OM TOC TC and higher CEC of rice strawcompost (Table 2) The highest rate of crude humic sub-stances (CHS3) showed the highest soil total N compared toother treatments and this was due to no N depletion in soilbecause the rice plants could not survive Normal fertilization(C2) and crude humic substances treatments (CHS1 CHS2and CHS3) showed similar effect on exchangeable NH

4

+ andavailable NO

3

minus The higher NH3

volatilization regardless oftreatment resulted in lower contents of exchangeable NH

4

+

and available NO3

minus in soil (Figure 2)


b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)

Figure 9 Treatments (C1 soil alone C2 soil + complete fertilization CHS1 soil + complete fertilization + 20 g rice straw compost + 2 gsawdust ash CHS2 soil + complete fertilization + 40 g rice straw compost + 4 g sawdust ash and CHS3 soil + complete fertilization + 60 grice straw compost + 6 g sawdust ash) effect on selected soil exchangeable cations (K+ Ca2+ Mg2+ Na+ Cu2+ Zn2+ Fe2+ and Mn2+) contentat 90 days after seeding Different alphabets indicate significant difference between means using Tukeyrsquos test at 119875 le 005 The error bars arethe plusmn standard error of quadruplicates


The effects of the different treatments on selectedexchangeable cations at 90 days of seeding are shown inFigure 9 The treatment with the highest rate of crude humicsubstances (CHS3) showed the highest soil exchangeable K+Ca2+ Mg2+ Na+ Zn2+ and Mn2+ compared with othertreatments due to less nutrients depletion in the soil as therice plants died during this study CHS1 CHS2 and CHS3increased exchangeable Ca2+ and Zn2+ compared to normalfertilization (C2)The treatment with the lowest crude humicsubstances (CHS1) showed the highest exchangeable Cu2+compared with other treatments because of antagonisticeffect of Cu and Zn [62] Soil exchangeable Fe2+ (CHS1 gtCHS2gtCHS3) decreasedwith increasing rate of crude humicsubstances (CHS1 ltCHS2 ltCHS3) due to increase in soil pH(Figure 7) [63]

In this present study the lowest crude humic substancerate (CHS1) is considered optimum rate for increasingMR219variety rice plantsrsquo dry matter production uptake of N crudeSi Ca Mg Zn Cu and Fe and recovery of N Mg Zn andCu However application of crude humic substances at therate of 40 g potminus1 (CHS2) showed similar effect as that ofCHS1 on plant height number of leaves tillers uptake of KP crude Si CaMg NaMn and Zn and recovery of P K andMg

4 Conclusions

Amending an acid soil (Typic Paleudults) with crude humicsubstances inwaterlogged condition increased ammonia lossHowever application of the lowest crude humic substancesrate (20 g potminus1) improved rice plant dry matter productionnutrients uptake recovery and soil chemical propertiesTherefore crude humic substances could be used to amendacid soils in flooded rice fields to improve MR219 rice plantgrowth and soil chemical properties but long term fieldevaluation is essential to consolidate the findings of thisstudy This aspect is being embarked on in our ongoing fieldexperiments

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

Authors acknowledge Ministry of Education (MOE)Malaysia for Long-term Research Grant Scheme LRGS(Food Security-Enhancing sustainable rice production) andUniversiti Putra Malaysia for funding this research project

References

[1] A R Zaharah H Zulkifli and H A H Sharifuddin ldquoEvalu-ating the efficacy of various phosphate fertiliser sources for oilpalm seedlingsrdquo Nutrient Cycling in Agroecosystems vol 47 no2 pp 93ndash98 1997

[2] K J Goh and P S Chew ldquoWorkshop on direct application ofphosphate rocks and appropriate technology fertilisers in Asiawhat hinder acceptance and growthrdquo in Direct Application ofPhosphates to Plantation Tree Crops inMalaysia pp 59ndash76 1995

[3] Y E Sallade and J T Sims ldquoPhosphorus transformationsin the sediments of Delawarersquos agricultural drainageways IIEffect of reducing conditions on phosphorus releaserdquo Journalof Environmental Quality vol 26 no 6 pp 1579ndash1588 1997

[4] G V Wilson F E Rhoton and H M Selim ldquoModelingthe impact of ferrihydrite on adsorption-desorption of soilphosphorusrdquo Soil Science vol 169 no 4 pp 271ndash281 2004

[5] H Y Chrsquong O H Ahmed and N M Majid ldquoImproving phos-phorus availability in an acid soil using organic amendmentsproduced from agroindustrial wastesrdquo The Scientific WorldJournal vol 2014 Article ID 506356 6 pages 2014

[6] R D Delaune andW H Patrick ldquoUrea conversion to ammoniainwaterlogged soilsrdquo Soil Science Society of America Journal vol34 no 4 pp 603ndash607 1970

[7] W Zhengping O Van Cleemput P Demeyer and L BaertldquoEffect of urease inhibitors on urea hydrolysis and ammoniavolatilizationrdquo Biology and Fertility of Soils vol 11 no 1 pp 43ndash47 1991

[8] J L Havlin J D Beaton S L Tisdale andW L Nelson Soil Fer-tility and Fertilizers An Introduction to Nutrient ManagementPrentice Hall Upper Saddle River NJ USA 6th edition 1999

[9] X-T Ju G-X Xing X-P Chen et al ldquoReducing environmentalrisk by improving Nmanagement in intensive Chinese agricul-tural systemsrdquo Proceedings of the National Academy of Sciencesof the United States of America vol 106 no 9 pp 3041ndash30462009

[10] S Moose and F E Below ldquoBiotechnology approaches toimproving maize nitrogen use efficiencyrdquo in Molecular GeneticApproaches to Maize Improvement A L Kriz and B A LarkinsEds vol 63 ofBiotechnology in Agriculture and Forestry pp 65ndash77 Springer Berlin Germany 2009

[11] A O Adesemoye and J W Kloepper ldquoPlant-microbes interac-tions in enhanced fertilizer-use efficiencyrdquoAppliedMicrobiologyand Biotechnology vol 85 no 1 pp 1ndash12 2009

[12] G-L Tang J Huang Z-J Sun Q-Q Tang C-H Yan andG-Q Liu ldquoBiohydrogen production from cattle wastewater byenriched anaerobic mixed consortia Influence of fermentationtemperature and pHrdquo Journal of Bioscience and Bioengineeringvol 106 no 1 pp 80ndash87 2008

[13] OK Borggaard B Raben-Lange A LGimsing andBW Stro-bel ldquoInfluence of humic substances on phosphate adsorptionby aluminium and iron oxidesrdquo Geoderma vol 127 no 3-4 pp270ndash279 2005

[14] P Hinsinger ldquoBioavailability of soil inorganic P in the rhizo-sphere as affected by root-induced chemical changes a reviewrdquoPlant and Soil vol 237 no 2 pp 173ndash195 2001

[15] N C Brady and R R Weil The Nature and Properties of SoilsPearson Education Cranbury NJ USA 13th edition 2002

[16] S G Sommer L S Jensen S B Clausen and H T SoslashgaardldquoAmmonia volatilization from surface-applied livestock slurryas affected by slurry composition and slurry infiltration depthrdquoJournal of Agricultural Science vol 144 no 3 pp 229ndash235 2006

[17] L Omar O H Ahmed and N M A Majid ldquoMinimizingammonia volatilization in waterlogged soils through mixing ofurea with zeolite and sago waste waterrdquo International Journal ofPhysical Sciences vol 5 pp 2193ndash2197 2010


[18] O Latifah O H Ahmed and A M N Muhamad ldquoAmmonialoss ammonium and nitrate accumulation from mixing ureawith zeolite and peat soil water under waterlogged conditionrdquoAfrican Journal of Biotechnology vol 10 no 17 pp 3365ndash33692011

[19] S Kasim O H Ahmed N M A Majid M K Yusop andM B Jalloh ldquoReduction of ammonia loss by mixing urea withliquid humic and fulvic acids isolated from tropical peat soilrdquoAmerican Journal of Agricultural and Biological Science vol 4no 1 pp 18ndash23 2009

[20] A A Reeza O H Ahmed N M N A Majid and M BJalloh ldquoReducing ammonia loss from urea by mixing withhumic and fulvic acids isolated from coalrdquo American Journal ofEnvironmental Sciences vol 5 no 3 pp 420ndash426 2009

[21] S Rosliza O H Ahmed and N M A Majid ldquoControllingammonia volatilization by mixing urea with humic acid fulvicacid triple superphosphate and muriate of potashrdquo AmericanJournal of Environmental Sciences vol 5 no 5 pp 605ndash6092009

[22] S Rosliza O H Ahmed N M Majid and M B JallohldquoReduction of ammonia volatilization through mixing ureawith humic and fulvic acids isolated from palm oil mill effluentsludgerdquo American Journal of Environmental Sciences vol 5 no3 pp 382ndash386 2009

[23] P Palanivell K Susilawati1 O H Ahmed and N M MajidldquoEffect of humin-urea-rock phosphate amendment on Bekenuseries (Tipik Tualemkuts) soilrdquoAfrican Journal of Biotechnologyvol 11 no 45 pp 10317ndash10321 2012

[24] P Palanivell O H Ahmed K Susilawati and M N Ab MajidldquoMitigating ammonia volatilization from urea in waterloggedcondition using clinoptilolite zeoliterdquo International Journal ofAgriculture and Biology vol 17 pp 149ndash155 2015

[25] HM Peech ldquoHydrogen-ion activityrdquo inMethod of Soil AnalysisPart2 C A Black D D Evans L E Ensminger J LWhite F EClark and R C Dinauer Eds pp 914ndash926 American Societyof Agronomy Madison Wis USA 1965

[26] A Piccolo Humic and Soil Conservation Humic Substances inTerrestrial Ecosystem Elseiver Amsterdam The Netherlands1996

[27] K H Tan Soil Sampling Preparation and Analysis CRC PressBoca Raton Fla USA 2nd edition 2005

[28] A Cottenie ldquoSoil testing and plant testing as a basis of fertilizerrecommendationrdquo FAO Soils Bulletin vol 38 pp 70ndash73 1980

[29] J M Bremner ldquoTotal nitrogenrdquo inMethods of Soil Analysis Part2 C A Black D D Evans L E Ensminger J L White F EClark and R D Dinauer Eds pp 1149ndash1178 American Societyof Agronomy Madison Wis USA 1965

[30] D R Keeney and D W Nelson ldquoNitrogen-inorganic formsrdquo inMethods of Soil Analysis Part 2 A L Page D R Keeney D EBaker RHMiller R J Ellis and JD Rhoades Eds AgronomyMonograph no 9 pp 159ndash165 ASA and SSSA Madison WisUSA 1982

[31] A Mehlich Determination of P K Na Ca Mg and NH4

pSTDP no 1ndash53 Soil Test Division Mimeo North CarolinaDepartment of Agriculture Raleigh NC USA 1953

[32] J Murphy and J P Riley ldquoA modified single solution methodfor the determination of phosphate in natural watersrdquoAnalyticaChimica Acta vol 27 pp 31ndash36 1962

[33] D L Rowell Soil Science Methods and Applications LongmanScientific amp Technical 1994

[34] S Paramananthan Soils of Malaysia Their Characteristics andIdentification vol 1 Academy of Sciences Malaysia 2000

[35] P Palanivell K Susilawati O H Ahmed and N M MajidldquoCompost and crude humic substances produced from selectedwastes and their effects on Zea mays l nutrient uptake andgrowthrdquo The Scientific World Journal vol 2013 Article ID276235 15 pages 2013

[36] B Chefetz P G Hatcher Y Hadar and Y Chen ldquoChemical andbiological characterization of organic matter during compost-ing of municipal solid wasterdquo Journal of Environmental Qualityvol 25 no 4 pp 776ndash785 1996

[37] A C Petrus O H Ahmed A M N Muhamad H M NasirandM Jiwan ldquoEffect of K-N-humates on drymatter productionand nutrient use efficiency of maize in Sarawak MalaysiardquoTheScientificWorldJournal vol 10 pp 1282ndash1292 2010

[38] O H Ahmed M H A Husni A R Anuar M M Hanafi andE D S Angela ldquoA modified way of producing humic acid fromcomposted pineapple leavesrdquo Journal of Sustainable Agriculturevol 25 no 1 pp 129ndash139 2005

[39] P Palanivell K Susilawati O Ahmed and A N MuhamadldquoEffects of extraction period on yield of rice straw composthumic acidsrdquo African Journal of Biotechnology vol 11 no 20pp 4530ndash4536 2012

[40] O H Ahmed H Aminuddin and A H M Hanif ldquoAmmoniavolatilization and ammonium accumulation from urea mixedwith zeolite and triple superphosphaterdquo Acta AgriculturaeScandinavica Section B Soil and Plant Science vol 58 no 2 pp182ndash186 2008

[41] K B Siva H Aminuddin M H A Husni and A R ManasldquoAmmonia volatilization fromurea as affected by tropical-basedpalm oil mill effluent (pome) and peatrdquo Communications in SoilScience and Plant Analysis vol 30 no 5-6 pp 785ndash804 1999

[42] Muda Agricultural Development Authority ldquoRice checkrdquo 2014httpwwwmadagovmysemakan-tanaman-padi

[43] Y A Liew S R S Omar M H A Husni M A Z Abidin andN A P Abdullah ldquoEffects of micronutrient fertilizers on theproduction of MR 219 rice (Oryza sativa L)rdquoMalaysian Journalof Soil Science vol 14 no 1 pp 71ndash82 2010

[44] Y Singh H C Sharma K Singh et al ldquoRice yield as affectedby use of biofortified straw compost combined with NPKfertilizerrdquo International Rice Research Notes vol 30 no 1 pp47ndash48 2005

[45] M Tejada and J L Gonzalez ldquoCrushed cotton gin compost onsoil biological properties and rice yieldrdquo European Journal ofAgronomy vol 25 no 1 pp 22ndash29 2006

[46] S R Dar T Thomas I M Khan J C Dagar A Qadarand M Rashid ldquoEffect of nitrogen fertilizer with mushroomcompost of varied CN ratio on nitrogen use efficiency carbonsequestration and rice yieldrdquo Communications in Biometry andCrop Science vol 4 no 1 pp 31ndash39 2009

[47] S Goyal D Singh S Suneja and K K Kapoor ldquoEffect of ricestraw compost on soil microbiological properties and yield ofricerdquo Indian Journal of Agricultural Research vol 43 pp 263ndash268 2009

[48] M Tejada and J L Gonzalez ldquoApplication of two vermicom-posts on a rice crop effects on soil biological properties and ricequality and yieldrdquoAgronomy Journal vol 101 no 2 pp 336ndash3442009

[49] TWatanabe L HMan DM Vien et al ldquoEffects of continuousrice straw compost application on rice yield and soil propertiesin the Mekong Deltardquo Soil Science and Plant Nutrition vol 55no 6 pp 754ndash763 2009


[50] A S F Araujo and R T R Monteiro ldquoPlant bioassays to assesstoxicity of textile sludge compostrdquo Scientia Agricola vol 62 no3 pp 286ndash290 2005

[51] H R Bozorgi A Faraji R K Danesh A Keshavarz EAzarpour and F Tarighi ldquoEffect of plant density on yield andyield components of ricerdquo World Applied Sciences Journal vol12 no 11 pp 2053ndash2057 2011

[52] Malaysian Meteorological Department ldquo10-Day Agromete-orogical Bulletinrdquo 2014 httpwwwmetgovmy

[53] S Yoshida D A Forno J H Cock and K A GomezLaboratory Manual for Physiological Studies of Rice LAGUNA3rd edition 1976

[54] A R Dobermann ldquoNitrogen use efficiencymdashstate of the artrdquoin Proceedings of the IFA International Workshop on Enhanced-Efficiency Fertilizers p 17 Frankfurt Germany June 2005

[55] SAS SASSTAT Software SAS Institute Cary NY USA 2008[56] L Bundan N M A Majid O H Ahmed M Jiwan and F R

Kundat ldquoAmmonia volatilization from urea at different levels ofzeoliterdquo International Journal of Physical Sciences vol 6 no 34pp 7717ndash7720 2011

[57] Y Avnimelech and M Laher ldquoAmmonia volatilization fromsoils equilibrium considerationsrdquo Soil Science Society of Amer-ica Journal vol 41 no 6 pp 1080ndash1084 1977

[58] D SMikkelsen S K DeDatta andWNObcemea ldquoAmmoniavolatilization losses from flooded rice soilsrdquo Soil Science Societyof America Journal vol 42 no 5 pp 725ndash730 1978

[59] F Gallardo-Lara and R Nogales ldquoEffect of the applicationof town refuse compost on the soil-plant system a reviewrdquoBiological Wastes vol 19 no 1 pp 35ndash62 1987

[60] C Yu H Liu Y Xing N S Manukovsky V S Kovalev andY L Gurevich ldquoBioconversion of rice straw into a soil-likesubstraterdquo Acta Astronautica vol 63 no 7ndash10 pp 1037ndash10422008

[61] C W Smith and R H Dilday Rice Origin History Technologyand Production Wiley Series in Crop Science John Wiley ampSons New York NY USA 2002

[62] R Kumar N K Mehrotra B D Nautiyal P Kumar and P KSingh ldquoEffect of copper on growth yield and concentration ofFe Mn Zn and Cu in wheat plants (Triticum aestivum L)rdquoJournal of Environmental Biology vol 30 no 4 pp 485ndash4882009

[63] S Gotoh and W H Patrick ldquoTransformation of iron in awaterlogged soil as influenced by redox potential and pHrdquo SoilScience Society of America Journal vol 38 no 1 pp 66ndash71 1974

Submit your manuscripts athttpwwwhindawicom

Nutrition and Metabolism

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Food ScienceInternational Journal of

Agronomy


International Journal of



Microbiology

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2014

AgricultureAdvances in


PsycheHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BiodiversityInternational Journal of


ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

GenomicsInternational Journal of


Plant GenomicsInternational Journal of


Biotechnology Research International


Forestry ResearchInternational Journal of


Journal of BotanyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

EcologyInternational Journal of


Veterinary Medicine International


Cell BiologyInternational Journal of


Evolutionary BiologyInternational Journal of



(NH4

)2

CO3

+ 2H+ 997888rarr 2NH+4

+ CO2

+H2

O (2)

NH+4

+OHminus 999445999468 NH3

+H2

O (see [8]) (3)

Thus the aforementioned problems lead to nutrients unavail-ability for rice plant growth and development To overcomethe stated problems farmers apply fertilizers excessively toattain higher yield However unbalanced use of N and Pfertilizers causes environmental problems such as eutroph-ication groundwater pollution acid rain deposition soilacidification and greenhouse gas emissions [9ndash12]

Utilization of humic substances in acidic soils wasreported not only to have reduced Al3+ and Fe2+ but also tohave increased P [13] Reduction of Al3+ and Fe2+ ions in soilsolution is essential as this prevents P from being precipitatedas strengite vivianite variscite and various minerals of theplumbogummite group [14]Moreover P fixation in acid soilscan be reduced by increasing soil pH as availability of P varieswith variation in soil pH For example most of P is availablefor plant uptake at neutral pH [8] This suggests that thesawdust ash used to extract crude humic substances in thisstudy can be exploited to increase pHof acidic soils because oftheir basic nature (pH 11) Crude humic substances which areproduced from rice straw compost and sawdust ash can alsobe used to improve soil chemical properties because theseorganic substances can increase soil pH and organic matter[15] Additionally the high CEC of rice straw compost canbe exploited to improve CEC of acid soils and to as wellretain cations such as NH

4

+ K+ Ca2+ andMg2+ In additiongood retention of cations including NH

4

+ ion ammoniavolatilization from urea and nutrients leaching could be sig-nificantly reduced Ammonia volatilization from urea as anexample can be reduced with application of materials whichare high in CEC [16ndash18] Humic substances which are highin CEC have been used to control ammonia volatilizationin nonwaterlogged condition In nonwaterlogged conditionshumic acids and fulvic acids from tropical peat coal palmoil mill effluent sludge and crude humins from composts[19ndash23] have been used to reduce NH

3

loss from urea Inwaterlogged soils Clinoptilolite zeolite has been used toreduce ammonia volatilization [17 18 24]

Apart from fewer studies which had been carried out todetermine the effects of humic substances on ammonia lossand soil chemical properties of waterlogged soil isolation(extraction fractionation and purification) of humic acidsfulvic acids and humins is laborious and expensive Hencein this present study rice straw compost was rather mixedwith sawdust ash to produce crude humic substances Wehypothesized that the application of crude humic substanceswhich are high in CEC could reduce NH

3

volatilization fromurea increase rice plant growth nutrients uptake recoveryand aswell improving soil chemical properties inwaterloggedcondition Thus this study was conducted to determine theeffects of mixing an acid soil (Typic Paleudults) with crudehumic substances at three rates (20 40 and 60 g potminus1) inwaterlogged condition on NH

3

volatilization from urea riceplant growth nutrients uptake and recovery and improve soilchemical properties

Table 1 Selected chemical properties of Typic Paleudults (BekenuSeries) soil before incubation and pot study

Property Currentstudy

Standard datarange

(0ndash36 cm)pHwater 441 46ndash49

Bulk density (g cmminus3) 116 NA

TOC () 143 057ndash251

Total N () 008 004ndash017

Exchangeable NH4

+ (mg kgminus1) 2102 NA

Available NO3

minus (mg kgminus1) 701 NA

Available P (mg kgminus1) 485 NA(Cmol (+) kgminus1)

CEC 1197 386ndash846Exchangeable K+ 010 005ndash019Exchangeable Ca2+ 025 NAExchangeable Mg2+ 034 NAExchangeable Na+ 022 NAExchangeable Fe2+ 019 NAExchangeable Cu2+ Trace NAExchangeable Zn2+ 001 NAExchangeable Mn2+ 002 NATotal titratable acidity 086 NAExchangeable H+ 064 NAExchangeable Al3+ 022 NANA not available Paramanathan [34]

2 Materials and Methods

21 Soil Sampling Preparation and Characterization TypicPaleudults (Bekenu Series) soil was sampled at 0 to 25 cmin an uncultivated area of Universiti Putra Malaysia BintuluSarawak Campus Malaysia (latitude 3∘121015840N and longitude113∘41015840E) The soil was air-dried ground and sieved to pass toa 5mm sieve The soil was analyzed before and after the potstudy for pH in distilled water (at ratio of 1 25 soil water)using a digital pH meter [25] total carbon using loss-on-ignition method [26] total organic carbon (TOC) andorganic matter (OM) content using Walkley-Black method[27] cation exchange capacity (CEC) using the ammo-nium acetate leaching method [28] total N using Kjeldahlmethod [29] and available NO

3

minus and exchangeable NH4

+

[30] Exchangeable cations and available P were extractedusing the Double Acid Method [31] after which cationswere determined using Atomic Absorption Spectrometer(AAnalyst 800 Perkin Elmer Instruments Norwalk CT)whereas available P was determined using the Blue Method[32] Total titratable acidity was determined using acid-basetitration method [33] The selected chemical and physicalproperties of the soil (Table 1) used in this study are typicalof Typic Paleudults (Bekenu series) and they are consistentwith those reported by Paramananthan [34] except for CECexchangeable calcium and magnesium










2

O5

130 kg haminus1K2




Sawdustash






0

1

2

3

4

5

6

0 5 10 15 20 25 30

Dai

ly am

mon

ia lo

ss

( o

f app

lied

N)


C1C2CHS1

CHS2CHS3


c

ba a a

020406080


Tota

l NH

3lo

ss (

)



(i) G1 100 sand














a a a a

0

20

40

60

80

100

120

G1 G2 G3 G4

Ger

min

atio

n ra

te (

)

Treatment

a

b b b

0

20

40

60

80

100

G1 G2 G3 G4

Shoo

t elo

ngat

ion

(mm

)

Treatment

a a a

0

20

40

60

80

100

120

Relat

ive g

erm

inat

ion

()

G2 G3 G4Treatment

a

b b b0

20

40

60

80

100

120

Root

elon

gatio

n (m

m)


a

aa

00

10

20

30

40

G2 G3 G4

Relat

ive r

oot e

long

atio

n (

)

Treatment

a

a

a

00

10

20

30

40

G2 G3 G4

Ger

min

atio

n in

dex

()

Treatment

aa a

0

5

10

15

20

25

30

G2 G3 G4

Relat

ive s

hoot

elon

gatio

n (

)

Treatment



b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100


Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1






4


3




3


3


4

+ ions to NH3


3




cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

































2

O5

130 kg haminus1K2




Sawdustash






0

1

2

3

4

5

6

0 5 10 15 20 25 30

Dai

ly am

mon

ia lo

ss

( o

f app

lied

N)


C1C2CHS1

CHS2CHS3


c

ba a a

020406080


Tota

l NH

3lo

ss (

)



(i) G1 100 sand














a a a a

0

20

40

60

80

100

120

G1 G2 G3 G4

Ger

min

atio

n ra

te (

)

Treatment

a

b b b

0

20

40

60

80

100

G1 G2 G3 G4

Shoo

t elo

ngat

ion

(mm

)

Treatment

a a a

0

20

40

60

80

100

120

Relat

ive g

erm

inat

ion

()

G2 G3 G4Treatment

a

b b b0

20

40

60

80

100

120

Root

elon

gatio

n (m

m)


a

aa

00

10

20

30

40

G2 G3 G4

Relat

ive r

oot e

long

atio

n (

)

Treatment

a

a

a

00

10

20

30

40

G2 G3 G4

Ger

min

atio

n in

dex

()

Treatment

aa a

0

5

10

15

20

25

30

G2 G3 G4

Relat

ive s

hoot

elon

gatio

n (

)

Treatment



b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100


Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1






4


3




3


3


4

+ ions to NH3


3




cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























0

1

2

3

4

5

6

0 5 10 15 20 25 30

Dai

ly am

mon

ia lo

ss

( o

f app

lied

N)


C1C2CHS1

CHS2CHS3


c

ba a a

020406080


Tota

l NH

3lo

ss (

)



(i) G1 100 sand














a a a a

0

20

40

60

80

100

120

G1 G2 G3 G4

Ger

min

atio

n ra

te (

)

Treatment

a

b b b

0

20

40

60

80

100

G1 G2 G3 G4

Shoo

t elo

ngat

ion

(mm

)

Treatment

a a a

0

20

40

60

80

100

120

Relat

ive g

erm

inat

ion

()

G2 G3 G4Treatment

a

b b b0

20

40

60

80

100

120

Root

elon

gatio

n (m

m)


a

aa

00

10

20

30

40

G2 G3 G4

Relat

ive r

oot e

long

atio

n (

)

Treatment

a

a

a

00

10

20

30

40

G2 G3 G4

Ger

min

atio

n in

dex

()

Treatment

aa a

0

5

10

15

20

25

30

G2 G3 G4

Relat

ive s

hoot

elon

gatio

n (

)

Treatment



b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100


Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1






4


3




3


3


4

+ ions to NH3


3




cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























a a a a

0

20

40

60

80

100

120

G1 G2 G3 G4

Ger

min

atio

n ra

te (

)

Treatment

a

b b b

0

20

40

60

80

100

G1 G2 G3 G4

Shoo

t elo

ngat

ion

(mm

)

Treatment

a a a

0

20

40

60

80

100

120

Relat

ive g

erm

inat

ion

()

G2 G3 G4Treatment

a

b b b0

20

40

60

80

100

120

Root

elon

gatio

n (m

m)


a

aa

00

10

20

30

40

G2 G3 G4

Relat

ive r

oot e

long

atio

n (

)

Treatment

a

a

a

00

10

20

30

40

G2 G3 G4

Ger

min

atio

n in

dex

()

Treatment

aa a

0

5

10

15

20

25

30

G2 G3 G4

Relat

ive s

hoot

elon

gatio

n (

)

Treatment



b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100


Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1






4


3




3


3


4

+ ions to NH3


3




cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























b b

a a

c0

20

40

60

80


b

b

a a

c0

5

10

15

20


dc

ab

e0

20

40

60

80


c

ba a

d0

20

40

60

80

100


Plan

t hei

ght (

cm)

Treatment

Dry

mat

ter p

rodu

ctio

n (g

hill

minus1)

Num

ber o

f till

ers h

illminus1

Num

ber o

f lea

ves h

illminus1






4


3




3


3


4

+ ions to NH3


3




cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























cc

ab


c

ba

b

0

20

40

60


c c

ba

0

2

4

6

8


c

b

a a

0

20

40

60

80


d c

a b

0

5

10

15

20

c c

a b

0

5

10

15



b b

a a

00

10

20

30

40

b b

a a

00

05

10

15



dc

a

b

c

b

a

b

0000

0010

0020

0030

0040



c

b

a

b

0

10

20

30

40


0

50

100

150

200

Crud

e Si u

ptak

e (g

hillminus

1)

N u

ptak

e (g

hillminus

1)

P up

take

(g h

illminus1)

Fe u

ptak

e (g

hillminus

1)

Cu u

ptak

e (g

hillminus

1)

00

02

04

06

Zn u

ptak

e (g

hillminus

1)

Mn

upta

ke (g

hill

minus1)

Na u

ptak

e (g

hillminus

1)

Mg

upta

ke (g

hill

minus1)

Ca u

ptak

e (g

hillminus

1)

K up

take

(g h

illminus1)



b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























b

a

b

0

20

40

60


c

b

a

0

10

20

30

40


b

a a

0

50

100

150

200


c

ab


c

a

b

0

10

20

30


b

a

b


0

05

1

15Cu

reco

very

(g h

illminus1)

Zn re

cove

ry (g

hill

minus1)

0

minus100

100

200

300

400

Mg

reco

very

(g h

illminus1)

K re

cove

ry (g

hill

minus1)

P re

cove

ry (g

hill

minus1)

N re

cove

ry (g

hill

minus1)








de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























de

c

b

a

45

50

55

60

65

70

75


pHw

ater

c

ab ab

b

a

0

5

10

15

20

25


Avai

labl

e P (m

g kgminus

1)

a

b b b b000

005

010

015

020

025

030


Exch

ange

able

Al3 +

(Cm

ol (+

) kgminus

1)

a

a

bb

b

0000

0050

0100

0150

0200

0250

0300

0350


Exch

ange

able

H+

(Cm

ol (+

) kgminus

1)

a

b

c cc

00

01

02

03

04

05

06

07


Tota

l titr

atab

le ac

idity

(Cm

ol (+

) kgminus

1)





d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























d dc

b

a

d dc

b

a

c cb

b

a

d d cb

a





01234567

012345

0

1

2

3

4

5

05

101520

3540

3025

67

8O

rgan

ic m

atte

r (

)To

tal c

arbo

n (

)

bb b

b

a


0

01

02

03

04

05

Tota

l N (

)

aa

a a a


02468

10121416

Avai

labl

e NO

3

minus(m

g kgminus

1)

c

abbc bc

a


010203040

6050

Exch

ange

able

NH

4

+(m

g kgminus

1)

CEC

(Cm

ol (+

) kgminus

1)

Tota

l org

anic

carb

on (

)


+ available NO3



minus




4

+ andavailable NO

3



4

+

and available NO3



b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014

























b b bb

a

0

2

4

6

8

10


d

cb b

a

0

2

4

6

8

10

12

14


cbc bc

b

a

0

2

4

6

8

10


bb b b

a

00

02

04

06

08

10

12

14


d

bc

a

c

b

000

002

004

006

008

010


cc

b b

a

000

002

004

006

008

010


c bc bcb

a

000

005

010

015

020


a

b ab

b

c

00

02

04

06

08


Exch

ange

able

K+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Ca2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mg2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Na+

(Cm

ol (+

) kgminus

1)

Exch

ange

able

Zn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Cu2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Mn2

+(C

mol

(+) k

gminus1)

Exch

ange

able

Fe2

+(C

mol

(+) k

gminus1)





4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014



























4 Conclusions




Acknowledgments


References





































































Journal of




Agronomy





Microbiology




Volume 2014











































































Journal of




Agronomy





Microbiology




Volume 2014
























research article improving lowland rice ( o. sativa l. cv

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