Response of some Chinese cabbage germplasms to the development, survival and reporductivity of cabbage aphid, Brevicoryne brassicae Link Lal O.P. Indian Agricultural Research Institute, Regional Station, Katrain, Kulu Valley, H.P. (India). Abstract Seedlings of ten germplasms of Chinese cabbage were transplanted in pots and studied for their response to the nymphal development, mortality of nymphs, weight of adults, reproductivity and mortality of adults of cabbage aphid, Brevicoryne brassicae Linn. The nymphal period ranged from 7 to 13 days and 20 to 65 per cent nymphal mortality occurred on different lines. The average weight of adults ranged between 0.450 mg and 0.585 mg and there was 30 to 88% adult mortality within 20 days of adult life span. The nymphal production ranged between 11.13 and 43.25 per adult. The fast developers were found more in weight and also produced more nymphs. The nymphal development was quick on EC 87694, Granat x Mustard, Wong Bok and EC 87885 and the nymphal production on these germplasms was 43.25, 42.35, 33.35 and 31.77, respectively. The nymphal mortality on these lines was 20 to 35 per cent. The development of nymphs was delayed by 3 to 4 days on EC 87884, Chihili and Granat; the nymphal production being 11.13, 1953 and 21.80, respectively. There was 50 to 65% nymphal mortality and 60 to 88% adult mortality on these germplasms. Petsai, Wong Bok x Muslard, and Petsai x Mustard showed medium response. Top |