Vol. 11, Issue 2 (2022)

Author(s):
Rakesh Kumar, Suresh M Nebapure, Sharma RK, Bishwajeet Paul, Sinha SR and Rekha Kumawat

Abstract:
Insect pests and their natural enemies utilize the volatile semiochemicals emitted from their hosts or from food plants infested by their hosts. Volatile compounds play a major role in the plant defense mechanisms against various insect pests. This study was conducted to test the behavioral responses of egg parasitoid Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) to synthetic herbivory induced plant volatiles, singly, and as combinations used in a Y-tube olfactometer bioassay. This study suggests that the highest significant responses of T. chilonis Ishii male and female were shown to Cis-hexanol and Cis-3- hexenyl acetate at 5 ppm and 10, when tested singly, over the control. Although, methyl salicylate (MeSA) at all concentrations tested, failed to elicit significant responses over the control in both sexes of T. chilonis Ishii. Interestingly, among the different combinations of synthetic herbivory induced plant volatiles higher responses of T. chilonis Ishii male and female over the control were recorded from methyl salicylate (MeSA) + β-caryophyllene + Cis-hexanol (1:1:1) at all concentrations tested (viz.,1, 5, 10 and 15 ppm). Behavioral study of T. chilonis Ishii has manifested the differential sensitivity to synthetic herbivory induced plant volatiles and different doses of these compounds.