Doctoral seminar- II(ENT- 692)

INSECT BIOTYPES

Submitted to:

Course Instructor: Dr. A. L. Narangalkar Head, Dept. of Agril. Entomology

Submitted by:

H. R. Sawai

Ph.D. Scholar (Regd. No. 126)

DEPARTMENT OF AGRICULTURAL ENTOMOLOGYCOLLEGE OF AGRICULTURE, DAPOLI

DR. BALASAHEB SAWANT KONKAN KRISHI VIDYAPEETH, DAPOLI - 415712, DIST - RATNAGIRI, (MS)

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DEPARTMENT OF AGRICULTURAL ENTOMOLOGYCOLLEGE OF AGRICULTURE,

DR. BSKKV, DAPOLI Name : H. R. Sawai Regd No. : 126

Degree : Ph. D. Discipline : Agril.Entomology

course No. : ENT-692 Course title : Doctoral Seminar - II

Course instructor : Dr. A. L. Narangalkar Date : 15-05-2012

Abstact - Insect Biotypes

The concept of insect biotypes has been around for 100 years, having been first touched upon by Walsh (1864). First biotype was recognized by Painter 1930 who referred to them as biological strain. The existence of biotype discovered by Painter 1930 on Hessian fly, Mayetiola destructor on resistance varieties of winter wheat. Biotype is known to occur in 36 arthropod species belonging to 17 families of five orders. Aphids constitute about 50 % of the spp. with known biotype (Dhaliwal and Arora 2006).

The continuous growing of insect resistant variety may lead to certain physiological and behavioral changes in insect pest. So that, they are capable of feeding and developing on resistant varieties (kogan, 1998). The biotypes are more prone in rice, wheat, soybean, vegetables crops. The main causes for occurrence of biotypes viz., genetic changes in insect pests, continuous growing of insect resistant varieties, single gene resistance and mutation. Biotype development is, one of the major constraints encountered in breeding programmers for varietal resistance (Dhaliwal and Arora 2006).

Q biotype whitefly reported from Queensland Australia and it is severe on vegetable crops but differs from B biotypes as Q biotype does not induce the physiological changes normally as B biotype, also it has the ability to develop resistance quickly to some insecticide groups, particularly if they are used repeatedly (Fancelli, and Vendramim, 2002). In 2010 the soybean aphid biotypes 3 have been identified by university of Illinois which can multiply on aphid resistant soybean varieties consisting Rag-1 and Rag-2 resistant gene (Hill et al. 2010). Presently in rice five biotypes of BPH, six in rice gall midge in India, seven in Russian wheat aphid have occurred.

For prevention of the insect biotype development systematic surveillance programme, adaptation of IPM, injudicious use of insecticides, sequential cultivar release, maintenance of refugia, and use of tolerant varieties and phytosanitary measures are to be utilized.

References

Dhaliwal, G.S. and Arora, R. (2006). Integrated Pest Management: Concepts and Approaches. Ludhiana,

Kalyani Publishers. Pp135-137.

Fancelli, M., and Vendramim, J. D. (2002). Development of Bemisia tabaci Gennadius biotype B on

Lycopersicon Spp. Scientia Agricola, 59: Pp.665-669.

Hill, C.B., Herman, T. K., Voegtlin, D. J. and Hartman, G. L. (2010). A New Soybean Aphid (Hemiptera:

Aphididae) Biotype Identified. J. Econ. Entomol., 103(2): 509- 515

Kogan, M. (1998). Integrated pest management: Historical perspectives and contemporary developments.

A. Rev. Ent, 43: 243-270.

www.planthealthaustrelia.com (Q biotypes whitefly)

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History of insect biotype

The concept of insect biotypes has been around for 100 year, having been first touched

upon by Walsh (1864).The existence of biotype discovered by painter 1930 on Hessian fly

Mayetiola destructor on resistance varieties of winter wheat. First biotypes were recognized by

Painter 1930 who referred to them as biological strain. Occurrences of gall midge biotype in

India were suspected by Khan and Murthy (1955) even when no resistance varieties were

developed (Benture et al 2003). Biotype development in Corn leaf aphid, Rhapalosiphum maidis

was first detected by Cartier and Painter 1956 was observation in population. Carties (1959)

demonstrated the existance of three Acyrthisiphon pisium biotype on peas in field and green

house.First biotype alfalfa aphid Theroaphis maculata was identified by Pesho et al. 1960

Arizona. Eastop (1973) reviewed the concept of biotype with particular reference to aphid and

suggested that the term was synonymous with clone. First reports of a newly evolved biotype of

B. tabaci, the B biotype, appeared in the mid-1980s (Brown et al., 1995). Commonly referred to

as the silverleaf whitefly or Poinsettia strain. Diehl and Bush ( 1984) have presented an

evolutionary and applied perspectives of insect biotype. Saxena and Barrion (1987) have listed

over 35 spp. of insect pest Agriculture importance for which biotype has been reported.

Willam and Shambaaugh (1988) used biological studies to demonstrate that two

Phylloxera biotype exited the clinton biotype unable to feed on concord and six other grape spp.

and concord biotype unable to feed on clinton and nine other spp. of grape. A detailed analysis

on gall midge biotypes in India has been made by Bentur et al in 2003.March 2005, University of

California and Arizona researchers identify Biotype Q on poinsettias. University of Illinois

researchers (May 2010) recently identified a new soybean aphid biotype that can multiply on

aphid-resistant soybean varieties.

Introduction

The continuous growing of insect resistant variety may lead to certain physiological and

behavioral changes in insect pest. So that they are capable of feeding and developing on resistant

varieties.The term biotype is generally used to describe a population of insects capable of

damaging and surviving on plants previously known to be resistant to other populations of the

same species (Kogan, 1994). Biotype refers to the populations within a species which can

survive on and destroy varieties that have gene for resistance (Heinrichs et al., 1985). Bohssini et

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al. (2001) insect biotype studies genotypic interaction between resistance in plant and virulence

gene in insect. The challenge for the host-plant resistance strategy is the constant development of

new biotypes that can overcome the resistance of deployed genes (Ratcliffe et al. 2000).In these

cases, an insect biotype is considered to be a population of insects that is able to survive,

reproduce on, and/or cause injury to a cultivated plant that is resistant to other populations of the

same species. Biotypes are morphologically similar with normal insect types but they are

physiologically differing from them.Biotypes are convenient and useful designations for applied

problems in agricultural pest management, especially involving host plant resistance. First,

biotypes are intraspeciÞc categories. Second, biotypes are usually morphologically

indistinguishable. Third, bio- types differ in expressed biological attributes (Claridge and et al

1983).

Biotype development is, one of the major constraints encountered in breeding

programmes for varietal resistance. (Dhaliwal and Arora, 2005). Biotypes are developed more on

varieties having more biochemical defense than the varieties offering physical defense. The

development of insect biotype has based has posed a serious threat to the success of plant

resistance for the management of insect pests. Aphids constitute about 50 % of the spp. with

known biotype (Dhaliwal and Arora. 2005) because of parthenogenesis. Although the occurrence

of biotype among insect is comparatively less frequent than in plant pathogen (Dhaliwal and

Arora, 2005).

Causes of insect biotype

1. Many factors are associated with the ability of an insect to overcome plant resistance.

2. Biotype are known to develops on varieties where antibiosis (biochemical defense) is the

major component of resistance and rarely develop on varieties where antixenosis or tolerance

is mechanism of resistance

3. The continuous growing of insect-resistant varieties may lead to development of biotype.

4. Biotypes of the insects are evolving as a result of selection pressure exerted by large scale

growing of resistant cultivars (Kindler, 1999; Naber, 2000).

Due to a high degree of host specificity, the insect may evolve into a resistance breaking biotype.

The widespread use of one resistance gene is decreasing the genetic diversity of a host.

As a result some insect species will break the resistance gene (Heinrichs, 2001).

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Use of multiple resistance genes conferring different causes of resistance.

Puterka and Burton (1990) reasoned that biotype developed from

1. Mutation or a Pre-existing variability of virulence: Even a single mutant aphid

capable of feeding on a resistant genotype can build up into a new biotype (Pathak,

1970). Insect biotypes are strains of the pest insect that mutate to express virulence

genes that overcome resistance.

2. Biotypes of the insects are evolving as a result of selection pressure exerted by large

scale growing of resistant cultivars. Resistance due to antibiosis will put high pressure

on biotype development. Biotype are known to develops on varieties where antibiosis

(biochemical defense)is the major component of resistance.

3. Resistance due to Antixenosis will put little pressure on biotype development.

Biotypes are known to rarely develop on varieties where antixenosis is mechanism of

resistance.

4. Complete tolerance will put no pressure on biotype development. Biotype not

develops on varieties where tolerance is mechanism of resistance

Example of insect biotype

Biotype are known to be occurs in 36 arthropod species belonging to 17 families of six

order (Saxena and Barrion, 1987). Aphids constitute about 50 % of the spp. with known biotype.

Ten of 18 are aphid species in which parthenogenic reproduction contribute greatly successfully

development of biotype (Smith, 2004).

1. Coleoptera

Species Common name Family Crop Biotype recent reference

Callosobruchus maculatus

Cowpea weevil Bruchidae Cowpea1

Shade et al. (1996)

Phaedonia inclusa

Soyabean weevilCuculionidae Soyabeen 1

Sitophilius oryzae

Rice weevilCuculionidae Corn wheat

2

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2. Diptera

SpeciesCommon

nameFamily Crop

Biotype no. Recent reference

Agromyzaoryzae

Rice leaf miner AgromyzidaeRice

2

Mayetiola destructor

Hessian fly CecidomyiidaeWheat, Barley

14Bohissini et al. 2001

Naber, 2000

Orseoliaoryzae

Asian rice gall midge

Cecidomyiidae RiceIndian -6Chinese-4

Katitar et al. 2000

Chloropsoryzae

Rice stem maggot

Chloropidae Rice2

Rhagolitiscerasi

CherryFruit fly

Tephritidae Cherry2

3. Lepidoptera

Species Common name Family CropBiotype no. Recent

reference

Ostrinia nubilalis

European corn borer

Pyralidae Corn4

Laspeyresia pomonella

Walnut Coddling Moth

TortricidaeApple,Walnut 3

Yponomeuta padells

Small ermine moth

YponomeutidaeApple,Walnut

1

4. Thysanoptera

Species Common name Family CropBiotype no. Recent

reference

Thrips tabaci Onion thrips Thripidae Tobbaco2

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5. Homoptera

Species Common name Family CropBiotype no. Recent

reference

Bemisia tabacci Whitefly Aleyrodide Cotton, Okra,Cassava,

9Cervera et al. 2000

Acyrthosiphon pisum Pea aphid Aphididae Alfalfa9

Zarrabi, 1995

Aphis kondi Aphid Aphididae 1

Zarrabi et al 1995

Amphoraphora rubi A. idaei

Raspbery Aphid Aphididae Beeries6

Panda and Khush 1995, Jones, 2000

Aphis craccivora Cowpea aphidAphididae Groundnut

Bush sitao25

Aphis fabae Bean aphid Aphididae Broad bean 2

Aphis gossypii Cotton aphid Aphididae Pepper 2

Aphis nasturtii Buckhorn aphid Aphidida Potato 2

Aulacorthum solani Green spotted potato aphid

Aphididae Potato 1

Brevicoryne brassicae

CabbageAphid

Aphididae Cabbage 2

Chaetosiphon fragaefoli

Strawberry aphid

Aphididae Strawberry 2

Dysaphis directa D. plantaginea

Apple aphid Aphididae Apple3

Morris, 1998

Eriosoma lanigerum Wooly apple

aphidAphididae Apple

3Young, 1982

Macrisiphum euphorbiae

Potato aphid Aphididae Potato 2

Myzus persicaeGreen peach

aphidAphididae Potato 3

Rhopalosiphum maidis

Corn leaf aphid AphididaeBarley,Corn,

Sorghum

55, 2

Panda and Khush, 1995

Rhopalosiphum padiOat-bird cherry

aphidAphididae Cherry 2

Schizaphis graminum Green bug AphididaeBarley, oat, sorghum,

wheat

11

Porter, 2000

Therioaphis maculataSpotted alfalfa

aphidAphididae Alfalfa

6Panda and Khush,

1995

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Diuraphisnoxia

Russian wheat aphid

Aphididae Wheat Zsuzsa, 2001

Mueleerianella farmaireiNephotettix virescens

Leaf hopperGreen leaf

hopperCicadellidaeCicadellidae

Rice

13(lab)

Panda and khush, 1995

Saisstia oleae Black scale Coccidae Melon 1

Nilaparvata lugensBrown plant

hopper DelphacidaeRice

5Heinrichs, 2001;

Huang, 2001

Lepidosahes ulmiOystershell

scaleDiaspididae Apple 2

DaktulosphairaVitrifoliae

Grapr phylloxera

Phylloxeridae Grapevine 2

Insect’s biotypes known in different crop pest systems

Rice

In brown plant hoppers five different biotypes have been reported from Indian. Most of

the biotypes having morphological variations among biotypes such as rostrum, legs and antennae

got modified both in males and females

BPH Resistance Varieties Released

The host resistance of rice against BPH was first reported for the variety Mudgo in 1969.

Following gene inserted in different variety of rice for development of resistance of brown plant

hopper.

Biotypes Location

Biotypes 1 & 2 Southeast Asia

Biotype 3 Philippines

Biotype 4 Indian subcontinent

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BPH Resistance Varieties Released

BPH Resistance Varieties BPH Resistance Gene

IR26, IR 1561-228-3 , Mudgo, TKM6 Bph 1 gene

IR36, IR38 ,ASD 7, IR1154-243 Bph 1 gene

IR50, IR60 , Rathu Heenati Bph 3 gene

Babawee Bph4

ARC10550 bph5 (Khush et al., 1985)

Swarnalatha Bph6 (Kabir and Khush, 1988)

T12 bph7 (Kabir and Khush, 1988)

Chin Saba bph8 (Nemoto et al., 1989)

Kharamana, Balamwee and Pokkali Bph9 (Ikeda, 1985)

Introgression line of O. australiensisBph10 (Jena and Khush, 1990).

Resistance and Susceptible to Insect Biotype

The following table shows that the different resistance varieties of rice develop biotypes.

Gene Resistance and susceptible to insect biotype

Bph3,bph4 Resistant to all four biotype

Bph5, Bph6, Bph7 Susceptible to biotypes 1,2,3, Resistant to biotype 4

Bph8, Bph9,Bph 10 Resistant to biotypes1, 2,3

Scheme for selection of new Biotypes of Nilaparvata lugens

BiotypeResponse of Cultivar

Resistance SusceptibleBiotype 1 IR26,ASD7,Rathu Heenati, Babawee TN1

Biotype 2 Rathu Heenati, Babawee, ASD7 IR26,TN1

Biotype 3 IR26, Rathu Heenati, Babawe ASD7,TN1

Biotype 4

Babawee(Coimbatore)RathuHeenati,Babawee (Bangladesh and hyderabad)

IR26,ASD7,Rathu Heenati (Coimbatore)IR26,TN1, ASD7(Bangladesh and Hyderabad

Insect biotype in rice gall midge (GM)

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The losses of rice due to rice gall midge are about – 477 thousand tons of grain or 0.8%

of total production (Rs 330 Crores) in India. The occurrence of biotype in India suspected by

Khan and Murthy in 1955.The Biotype developed in rice gall midge in Indian-6 and Chinese-4

(Katiyar et al 2000).Genetic studies have identified, so far, 10 major genes conferring resistance

(Kumar et al., 2005). Most of the 60 plus gall midge resistant rice varieties developed to date

contain one of the three major genes viz., Gm1, Gm2 and an unidentified gene(s) in Ptb21

conferring immune level of resistance. Six distinct gall midge biotypes have been characterized

so far the reaction of biotype among different group of cultivars of rice against rice gall midge is

follows.

Biotype in rice gall midge

Biotype Location

1 Andhra Pradesh, Tamil Nadu, Chhattisgarh, Madhya Pradesh

2 Orissa, Maharashtra, Karnataka

3 Bihar, Manipur

4 Andhra Pradesh, Maharashtra (Sakoli)

5 Kerala

6 Manipur

Important biotype in whitefly Bemisia tabaci

Common names of whitefly are Tobacco whitefly, Sweet potato whitefly, Cotton

whitefly.The host of whitefly are Cassava, Cotton, Sweet potatoes, Tobacco,

Tomatoes ,Capsicum, Cucurbita pepo, Cucumbers , Hibiscus, Gerbera, lettuces, poinsettia,

soybeans, green beans, cabbage, broccoli, cauliflower. Bemisia tabaci (Gennadius), is one of the

most devastating pest insects of agriculture and horticulture in the world (Denholm et al. 1996)

but it is also an efficient vector of a great many plant viruses (Brown 2007). The pest status of

this insect is further complicated by the recognition of more than 20 distinct strains or biotypes

worldwide(Brown et al. 1995; Perring 2001).Of these, the B(silverleaf whitefly or poinsettia

strain) and Q biotypes represent the greatest threat to growers.

First reports of a newly evolved biotype of B. tabaci, the B biotype, appeared in the mid-

1980s (Brown et al., 1995) B biotype has been shown to be highly polyphagous. The B biotype

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is able to cause phytotoxic disorders in certain plant species, e.g. silverleaf in squashes

(Cucurbita sp.) Although indistinguishable in appearance from silverleaf whitefly (biotype B),

these insects are much less susceptible to insect growth regulators and many neonicotinoid

insecticides. The Q biotype was detected in the United States in 2004 on greenhouse poinsettia

plants (Dennehy et al. 2005). Q-biotype populations are generally less susceptible to many

insecticides currently used in this country, including pyriproxifen (Distance), buprofezin (Talus,

Applaud), imidacloprid (Marathon), thiamethoxam (Flagship), and acetamiprid (Tristar).

Important biotype in soyabean aphid

Rhamnus cathartica L.(buckthorn) is the primary or overwintering host ofA.glycines on

which sexual reproduction occurs; how-ever, eggs can be laid on Rhamnus alnifolia L. (Voegtlin

et al. 2004). Soybean aphids are the No. 1 insect threat to soybean production in the North

Central region of the United States.Soybean is the most important secondary or summer host of

A. glycines (Hill et al. 2004). Soybean aphid has the ability to transmit plant viruses to soybean

such as Alfalfa mosaic virus, Soybean dwarf virus, and Soybean mosaic virus (Hartman et al.

2001, Hill et al. 2001, Clark and Perry 2002, Wang and Ghabrial 2002, Domier et al. 2003).

Earlier study identifying a soybean aphid biotype that could colonize plants with the

Rag1 resistance geneThis gives the pest a high potential to adapt to and reduce the effective life

of resistance genes deployed in production." When farmers plant aphid-resistant soybean

varieties, they provide protection against Biotype 1. However, recent research indicates that

Biotype 2, which was first discovered in 2006, can overcome some aphid-resistant varieties

University of Illinois researchers recently identified a new soybean aphid biotype that can

multiply on aphid-resistant soybean varieties The most recently identified soybean aphid,

Biotype 3, was discovered in Springfield Fen, Ind., on an overwintering host, glossy buckthorn

They found it was capable of feeding and multiplying on varieties carrying the resistance genes

Rag1 and Rag2. Biotype 3 was capable of feeding and multiplying on varieties carrying the

resistance genes Rag1 and Rag2 in soybean.Other resistance genes against soybean aphid Rag 3

Rag 4, are currently on the breeding pipelines for incorporation into elite varieties to suppress

biotype 3

Prevention of Insect Biotype Development

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Systemic surveillance programme should be designed for monitoring the insect biotype

development. (Ratcliffe, 2001).

Adaptation of integrated pest management techniques likes inters- cropping mixed

cropping.  

Reduction of the alate phase will slow down the development of the insect towards a

resistance breaking biotype.

Use of insect growth regulator:

Example-Buprofezin inhibits acetylcholinesterase activity in B-biotype Bemisia tabaci

(Cottage and Gunning, 2006).

Use good non-chemical controls: Remove older leaves, keep areas free from weeds,

segregate infested from non-infested plants, discard heavily infested material.

E.g. Q biotype of white flies (Sanderson et al 2005). Insecticides for rotation include

Azatin, Insecticidal soap, Horticultural oil, Botanigard etc.

No single control treatment can be used on a long-term basis against this pest.Example:

There have also been good results with applications of Orthene followed several days

later by a pyrethroid. Give good result to control Q and B biotype of white fly.

(Sanderson et al 2005).

Maintenance of Refugia: Provide harborage for susceptible moth production to reduce the

chance of resistant (R).To support avirulent individuals to mate with virulent individuals

in the insect population.

Use of susceptible cultivars for at least 20% of the growing area to offer refugees to the main

avirulent biotype in the insect population. (Sloderbeck, 1997 and Kerlin, 2002).

1. To preserve and promote the activity of parasites and predators.Avoid the use of broad-

spectrum insecticides such as pyrethroids, organophosphates, Oraganochlorine.

2. Increasing the number of miner gene in a variety may enhance the level of horizontal

resistance and its stability.

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1. Miner gene may be combined with major gene.

2. Gene rotating: Use cultivars with one gene in one season, then a different resistance

gene the next (gene rotation).To minimize selection pressure on given resistance

varieties on insect population may be reduced.

3. DNA marker technology is currently used to map and identify specific gene structures

conferring resistance traits in plants. Understanding the genetics of resistance in plants will

provide the knowledge to improve resistance deployment strategies.

4. Use of tolerant cultivars that tolerant varieties would not only check yield loss caused by

insects, but this character combined with major genes.

5. Crop multiline: Different resistance genes in different plants of the same crop within a single

field of area

6. Sequential cultivar release: Use until failure, switch to next gene or when varieties with a

major gene become susceptible due to selection for new biotype another a variety with a new

major gene for resistance is released.

7. Gene pyramiding combines multiple resistance genes (against one pest) in the hybrid or

cultivar OR two or more major gene for vertical resistance is incorporated into a variety to

impart resistance to more biotype. Since monogenic resistance is generally more vulnerable to

biotype development than polygenic resistance.

8. Phytosanitary risk

Very few countries remain free from B. tabaci, illustrating the difficulty of preventing its

movement in international trade. Emergence of the B biotype of B. tabaci, with its ability to feed

on many different host plants has given whitefly-transmitted viruses the potential to infect new

plant species.(Tobacco leaf curl, transmissible tomato yellow leaf curl bean golden mosaic,

squash leaf curl. Particular attention is needed from countries where certain B. tabaci isted

viruses.

Conclusion

Insect biotypes are main limitation of host plant resistance.

An average period of 5-8 years is required for development of variety; however, it has taken less

than 10 years for breakdown of resistance in the field. Insect biotypes are more developed in

Homopteran insect (50% in aphids). Developed more on varieties having more biochemical

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defense than the varieties offering physical defense. Monogenic resistance is generally more

vulnerable to biotype development than polygenic resistance.

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Claridge, K. L. ( 1983). The biotype concept and its application to insect pests of agriculture.

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Dhaliwal, G.S. and Ram Singh, (2004). Host plant resistance to insect: Concepts and

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Dhaliwal, G.S. and Ramesh Arora (2006). Integrated Pest Management: Concepts and

Approaches. Ludhiana, Kalyani Publishers. Pp.135-137.

Fancelli, M. and Vendramim, J. D. (2002). Development of Bemisia tabaci Gennadius biotype B on

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Frank B. P., Puterka, G. J., Hammon, R. W., Burd, J. D., Randolph, T., and Rodney , W. C.,

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Heinrichs, E. A. (1988). Plant stress- Insect interaction. John Wiley & Sons, New York, USA.

Heinrichs, E. A. (2001). Development of multiple pest resistance crop cultivars. J. Agric. Ent. 11: 325-

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Hill, C.B., Herman, T. K., Voegtlin, D. J. and Hartman, G. L. (2010). A New Soybean Aphid

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Ikeda R, Kaneda C. 1985. Genetic analysis of resistance to BPH Nilaparvata lugens Stål in rice.

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J. A. Webster and D. R. Porter. 2000. Plant Resistance Components of Two Greenbug

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