Assessment of suitability of different growth stages of Chilo tumidicostalis Hmpsn for development of parasitoid Cotesia flavipes Cam in Assam

Host stage of Chilo tumidicostalis Hmpsn suitability for parasitization by Cotesia flavipes Cam and its development were studied under confinement. The adults of C flavipes preferred IV instar followed by V and III instar larvae of host C tumidicostalis by 80, 70 and 60 per cent respectively. On the other hand it was found that incubation and larval periods were longest in III instar (9.91 days) and shortest in VII instar (7.90 days) larvae. The pre-pupal and pupal periods of parasitoid larvae emerged from III instar host were longest (6.29 days) and in VI instar larvae it was shortest (6.01 days). This study revealed that although parasitoid preferred IV instar larvae for parasitizing but growth and development were found highest in VI instar larvae.