Biological parameters and thermal requirements of Trichogramma chilonis reared on Corcyra cephalonica and Plutella xylostella eggs

The objective of this work was to determine the biological parameters and thermal requirements of Trichogramma chilonis strain reared on Corcyra cephalonica and Plutella xylostella eggs at College of Agriculture, CAU, Imphal, Manipur. The optimum temperature for the parasitism and emergence of T. chilonis was 25°C and the utmost longevity was found at the same temperature. Maximum parasitism was observed 84.14 and 82.71 per cent at 25°C, while minimum parasitism was 76.57 and 69.14 per cent at 20°C on C. cephalonica and P. xylostella eggs, respectively. The results indicate that temperature has a significant effect on the biological parameters of T. chilonis and with increasing temperature developmental duration decreased in laboratory condition of Manipur. On the basis of the present results Corcyra cephalonica eggs was more suitable for mass production of T. chilonis than P. xylostella under controlled conditions.