Host plant resistance against sesame leaf webber and capsule borer, Antigastra catalaunalis Duponchel (Pyraustidae: Lepidoptera)

Abstract

A study was conducted to identify a resistance source against sesame leaf webber and capsule borer, Antigastra catalaunalis (Dup.) among 43 sesame genotypes under field and laboratory conditions. The reaction of genotypes was categorized using 0 to 9 scoring methodology. The genotypes KMR 14 and TKG 22 were found as moderately resistant with the score of 3 and grade 5 while SI 250, ES 22 and UMA were rated to be resistant with the score 1.6 and grade 3. Among 23 genotypes tested for biophysical (non-preference) and biochemical basis (antibiosis) of resistance three genotypes viz., ES 22, UMA, SI 250 and KMR 14 were identified as less preferred for oviposition with the lowest number of eggs laid on UMA. The egg laying of A. catalaunalis was positively correlated with the trichome density on the leaf. The low growth index of A. catalaunalis in the resistant genotypes ES 22, SI 250 and UMA indicates the presence of antibiosis mechanism in the genotypes. Hence, these genotypes could be used as resistant source in hybridization programmes for transferring leaf webber and capsule borer resistance.