Mechanism of Resistance to Helicoverpa armigera (Lepidoptera: Noctuidae) in Chickpea: Role of Oxalic Acid m Leaf Exudate as an Antibiotic Factor

Abstract

Mechanisms of resistance to Hrlicooeq~c~ cln~tigcv-rr Hi1l)rier in cllickpen, Cicer urit.tinurn L., were investigated. Inhihition of hrvd growth occiirred i n a feeding test using the leaves of chickpea genotypes, which had previously bee11 identified as having resistilnce to H , crn~ligeru. A feeding test using unwashed ilnd washed leaves revealed tl~i~t tht. si~bstancr responsible for the growth inhibition was water so111I)le ;md resent on the srlrfilce of the leaves. Acid co~npo~~ents of the leaf exr~tli~te were imi~lyzed by !ig~l-~erfornl~illCr liqaid c11romatography. Oxalic acid and rnalic acid were detected as tniijor colnponrnts in ull 4 genotypes that were analyzed. Genotypes resistant to H. e~n~tigerrl ;~ccrinnllated Inore oxalic ticid on the leaves than sr~sceptiblr genotypes. Oxalic acid showcd significant growtli inhillition on H. ctn~tigc?rcr larviir when incl~ided in a semi-;~rtificiel diet. Tlie i~c*crlmlllotion ol' oxalir ;tcid is consitlered to be one of the mecl~anislns of H. rln~tigcv-r~ resistance ill chickpri~. Inhibition of larvill growth by oxalic acid was not r*aused I)y antifeediint effects 1)rrt was Inore likely i~ttrihutable to antibiosis. Miilic acid J~ad n o effect on Iiirval growtli.. . KEY WORDS liost plant resistance, growth inhibition, rnalic ilrid Helicourr)~n nnnigbra HUBNER is a serious pest on a wide range of crops including chickpea, Cicrr aric~tini~rn L.; pigeonpea, Cnjnntrs crzjai~ (L,.) Millsp.: s~lnflower, Helinnthus nnttr~us L.; maize, Zen iruiys L.; sorghum, Sorghum bicolor (L.) Moerlch; tomato, Lycopemicon esu~lenturri (Mill); and cotton, Govsypium spp. On chickpea, H, arntigern is commonly known as the gram pod Imrer, and causes substantial crop losses in alrnost all couritries where chickpea is grown. Several chickpea genotypes have been identified with exploitable levels of resistance to H. arrrtigeru (Dias et al. 1983. Lateef 1985, Lateef and Sachan 1990). These genotypes frequently suffer lower pod damage relative to susceptible genotypes. Antibiosis and oviposition antixenosis were reported as mectianisms of H. armigera resistance in some chickpea

Expression of resistance to the pod borer Helicoverpa armigera (Lepidoptera: Noctuidae), in relation to high-performance liquid chromatography fingerprints of leaf exudates of chickpea

“…Oxalic acid inhibits the growth of H. armigera larvae when incorporated in artificial diet, while malic acid shows no such effects (Yoshida et al, 1995(Yoshida et al, , 1997. Acetic acid showed a negative association with larval weight gain, and H. armigera damage rating at flowering and at maturity, while citric acid showed a negative and significant association with leaf damage at flowering.…”

“…Acidic exudates produced by the trichomes on the surface of chickpea plants, of which malic acid and oxalic acid are the principal components, result in oviposition non-preference and antifeedant effects on H. armigera Yoshida et al, 1995). The present studies focused on estimation of acid exudates in the leaf samples of a diverse array of chickpea genotypes to assess the possibilities of using high performance liquid chromatography (HPLC) fingerprints for the organic acids as markers to breed for resistance to H. armigera.…”

Interaction between host plant resistance and biological activity of Bacillus thuringiensis in managing the pod borer Helicoverpa armigera in chickpea

“…However, C 235 also resulted on adverse effects on H. armigera in combination with Bt, although it had low amounts of oxalic acids, but considerably high amounts of malic acid in the leaf exudates. Expression of resistance to pod borer, H. armigera is influenced by the pH and amounts of malic and oxalic acids in the leaf exudates (Bhagwat et al, 1995;Yoshida et al, 1995Yoshida et al, , 1997 and reduced larval and pupal weights and prolonged larval and pupal periods have been observed in insects reared on leaves, pods and in artificial diets impregnated with lyophilized leaves and pods of H. armigera-resistant genotypes of chickpea as compared to those of the susceptible ones (Sreelatha, 2003;Narayanamma et al, 2008 Figures followed by the same letter within a column do not differ significantly at P < 0.05. -= There was no larval survival.…”

The effect of nitrogen fertilization and rust fungus infection, singly and combined, on the leaf chemical composition of Rumex obtusifolius

“…Oxalic acid is one of the few toxic organic acids found in plants (Kingsbury 1964), it is a homopteran feeding inhibitor (Yoshihara et al 1980), it was deleterious to the aphid Myzus persicae reared on artificial diets (Massonie 1980) and leaf tissues of Ilex opaca containing calcium oxalate crystals were avoided by the leaf miner Phytomyza iliciola (Kimmerer & Potter 1987). However, oxalic acid was a phagostimulant for G. viridula (Renner 1970) and although also a phagostimulant for larvae of Helicoverpa armigera feeding on chickpea, Cicer arietinum, it was also a larval growth inhibitor for H. armigera (Yoshida, Cowgill & Wightman 1995). It is not known if oxalic acid has a similar deleterious effect on G. viridula.…”