Effect of Indian mustard on feeding,larval survival and development of Plutella xylostella at constant temperatures

Feeding behavior of Plutella xylostella under optional to non-optional conditions was studied at 10°C, 15°C, 20°C, and 25°C on Indian mustard, Brassica juncea. The study reveals that the variety Pusa Bahar was significantly less preferred by the larvae as compared with Pusa Bold and Varuna under optional to non-optional conditions. Larvae of P. xylostella consumed more food at 25°C than 20°C, 15°C and 10°C. Larval survival was found to be highest on cabbage (control) as compared with Indian mustard and was found to vary with host plants and temperature. The larval survival decreased to 11.29% on Pusa Bahar at 10°C. Increasing the temperature from 10°C to 20°C, larval mortality resulted more on Varuna than Pusa Bahar and Pusa Bold. Developmental period was prolonged on Pusa Bold at 10°C while it was shortest on cabbage at 25°C. A total of 536.47 degree days were required to complete the development by immature stages on Varuna at 25°C and 421.64 degree days on cabbage.