Department of Entomology and Agricultural Zoology, Tirhut College of Agriculture, Rajendra Agricultural University, Dholi, Muzaffarpur-843 121, Bihar (India).
Laboratory studies on post-embryonic development, survival rate and predation potential of Coccinella septempunctata Linn., a common predator of the mustard aphid (Lipaphis erysimi Kalt.) were undertaken. During the peak period, i.e., February-March, 1991 the minimum, maximum and average larval duration of C. septempunctata varied from 10.0–11.0, 16.0–17.0 and 13.0–14.0 days, respectively. On an average, 87.5–91.35 per cent of the larvae underwent pupation. The mean longevity of adult coccinellid was higher in February (16.73 days) than in March (13.52 days). The predation capacity of its adult (av. 78–80 nymphs) was greater than the larvae (av. 56–57 nymphs). The older larvae consumed more number of aphid nymphs per day than the younger ones.
