Influence of castor genotypes with different wax blooms on oviposition preference of endolarval parasitoid Snellenius maculipennis (Szepligate) of castor semilooper Achaea janata L

Abstract

The A. janata larvae reared on susceptible genotype DPC-9 had significantly greater parasitisation by S. maculipennis than the moderately resistant genotype 48-1 and resistant genotype GCH-4 tested under no-choice, dual-choice and multi-choice conditions, suggesting that host genotypes plays a significant role in the effectiveness of S. maculipennis in parasitisation of A. janata larvae. The increased parasitism of A. janata larvae by S. maculipennis on the susceptible genotype DPC-9 might be due to the fact that the host larvae was healthy on the susceptible genotype because lack of resistance to the herbivore. Percentage parasitism was greater under no-choice condition as compared to that under multi-choice and dual choice conditions, which may be largely because of non-availability of alternate host plant to the females of S. maculipennis in no choice condition. The genotype DPC-9 was hospitable to S. maculipennis, better suited for use in integrated pest management to minimize the losses due to A. janata in castor.