Biology and life table of Diaeretiella rapae against Brevicoryne brassicae on different cultivars of cauliflower

Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) is one of the most promising, effective and a common endoparasitoid of different aphid species including cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae). The present investigation was undertaken to study the influence of different cauliflower cultivars (Early London, PSBK-1, PSBK-25, Pusa Himjyoti and Snowball Super) on the cabbage aphid and biological growth parameters of its parasitoid, D. rapae . Parasitoid took maximum time to complete its life cycle from egg to adult emergence on cv. PSBK-25 and minimum on cv. Snowball Super. The adult female and male longevity were maximum on cv. PSBK -1 i.e., 7.8 days and 6.7 days, respectively. The fecundity of the parasitoid was similar for both PSBK-1 and PSBK-25. Gross reproductive rate ( GRR ) of the parasitoid was maximum on PSBK-1 and minimum on Snowball Super. The intrinsic rate of increase (r) of the parasitoid was maximum on Snowball Super and minimum on PSBK-25 while doubling time was higher on PSBK-25 and lower on Snowball Super. Hence, cauliflower cv. PSBK-1 can be exploited for mass production of D. rapae in pest management programme .