Cotesia flavipes Cameron parasitizing Chilo partellus (Swinhoe): Host-age dependent parasitism, cocoon formation and sex ratio

Investigations on parasitization of different host ages (5 to 20 days old) of Chilo partellus larvae by Cotesia flavipes were carried in the laboratory conditions at 27±2°C and 75±5 per cent relative humidity. Higher parasitization and cocoon formation was recorded on the 17 and 20 day old larvae of C. partellus with 82.61 and 82.46 per cent parasitization and 43.09 and 42.70 cocoon formation, respectively while no parasitization and cocoon was recorded in 5 day old larvae. The 11 and 14 day old larvae were highly preferred recording significantly more female progeny and on par with 17 and 20 days old larvae.