Comparison of some life history parameters between alate and apterous forms of turnip aphid (Homoptera : Aphididae) on cabbage under constant temperatures

Development, longevity, survivorship and fecundity of the alate and apterou s forms of the turnip aphid, Lipaphis erysimi (Kaltenbach), were studied on cabbage under constant temperatures in the laboratory. The developmental d urations for alate nymphs were 15.8, 9.5, 8.0 and 5.4 d at 15, 20, 25 and 3 0 degreesC, respectively, and those for apterous nymphs were 13.9, 6.8, 6.1 and 5.0 d. Alate nymphs developed 1.9-3.0 d longer at 15, 20 and 25 degree sC than the apterous nymphs, but the developmental durations between the al ate and apterous forms were not significantly different at 30 degreesC. The longevities of alate adults were 12.6, 17.7, 17.6, and 17.2 d at 15, 20, 2 5, and 30 degreesC, respectively, compared with 25.3, 21.3, 17.5 and 11.7 d , respectively, for apterous aphids under the corresponding temperature reg imes. Fecundity was also significantly less for alate adults than for apter ous adults. Alate adults produced an average of 7.9, 37.9, 39.0, and 11.9 n ymphs in their lifespan at 15, 20, 25 and 30 degreesC, respectively, compar ed with 52.5, 90.8, 83, and 29.7 nymphs per apterous adult at the same temp erature regimes.