Biology and feeding potential of Coccinella septempunctata (Linn.) against Lipaphis erysimi (Kalt) at different temperature regimes

Abstract

Biology and feeding potential of Coccinella septempunctata (Linn.) were studied in laboratory on 3rd instar nymphs of mustard aphid (Lipaphis erysimi Kalt.) at two different temperature regimes. At 30± 20C, fecundity, oviposition period, hatchability of eggs, male and female longevity (232±70.46, 12.8±3.91, 82.87±6.66, 22.70 ± 2.21
and 26.60 ± 4.45, respectively) were higher and incubation period, pre-oviposition period, total grub duration and pupal duration (2.6±0.51, 6.5±3.53, 8.7 ± 1.63 and 5.1 ± 1.10, respectively) were lesser in comparison to 25± 20C where fecundity, oviposition period, hatchability of eggs, male and female longevity, incubation period, preoviposition period, total grub duration and pupal duration were 169.8±61.12, 7.9±1.37, 71.68±4.08, 16.2 ± 1.31 and 21.50 ± 1.95, 2.9±0.73, 7.7±2.49, 11.1 ± 1.52 and 5.8 ± 0.918, respectively . At 27± 2 0C, total mustard aphid consumption by a grub of C. septempunctata during the whole life span, was 424.4±2.78 mustard aphids in comparison to 272.64±1.79 mustard aphid at 23± 20C. Similarly an adult male and female consumed 103.2±1.52 and 116.6 ±1.46 aphids per day respectively at 27± 2 0C in comparison to 65.6 ± 1.02 and 71.8 ± 1.60 at 23± 20C. Thus, at both temperatures aphid consumption increased gradually till 4th instar and 30±20C was found to be most suitable temperature as compared to 25±20C for the life history of C. septempunctata. Hence, it could be concluded that C. septempunctata might play a suitable role in biointensive Integrated Pest Management programme because of better longevity and high predatory potential against the mustard aphid.