Biology of the Mustard Aphid, Lipaphis erysimi,1 in India2

The mustard aphid, Lipaphis erysimi (Kaltenbach) (= Hyadaphis pseudobrassicae (Davis), the turnip aphid, in America), is a serious pest of cruciferous crops in India. The aphid appeared on radish in the field in late November and disappeared in early March. Under laboratory conditions the average prereproductive period, reproductive period, post reproductive period, and total longevity of apterous aphids varied from 5.80 to 9.55, 5.85 to 14.10, 0.95 to 1.55, and 12.60 to 25.20 days, respectively. The longest periods occurred in January, with the lowest temperature (23.72°C). The shortest periods occurred in February, with the highest temperature (28.36°C). At an average low temperature differ of 7.22°C maintained in a refrigerator the aphid started reproducing 52.8 days after birth and reproduction continued for 18 days. The average rate of reproduction per female per day and the total production per aphid under laboratory conditions varied from 4.02 to 5.28 and 30.9 to 60.7 nymphs, respectively, in apterous forms. Comparable figures for alate forms were 3.62 to 5.00 and 29 to 48, respectively. The average rate of reproduction per female per day and the number of nymphs produced per aphid at a low temperature of 7.22°C was 0.89 and 16.0, respectively.