Comparative Biology of Three Coccinellid Predators on Cowpea Aphid Aphis Craccivora

Abstract

Laboratory experiment was conducted to study the biology of coccinellid predators from agroecosystems of Odisha. About 17 species were identified, the most important being Coccinella septempunctata, Coccinella transversalis and Cheilomenes sexmaculata predating on aphids infesting cowpea. The biology of these when evaluated indicated that C. septempunctata was the largest, and C. sexmaculata the smallest; grubs of all the three are susceptible to the rising temperature. The total developmental period was maximum during January and the least during May for all species. Total larval period was 11.9 ± 2.34, 12.1 ± 6.19 and 12.6 ± 0.01 days in January and 8.2 ± 0.07, 7.00 ± 0.01 and 7.9 ± 0.06 during May with C. septempunctata, C. transversalis and C. sexmaculata, respectively; developmental periods for these were observed to be 22.4 ± 0.67, 20.2 ± 1.46 and 17.4 ± 0.82 days during January, and 15.2 ± 0.01, 11.5 ± 0.39 and 12.3 ± 0.61 days during May, respectively. Prepupae and pupae were the least affected by the fluctuations in temperature.

Seed Yield Improvement in Vigna unguiculata (L.) (Fabaceae): Efficiency of Pollinators and Impact of Aqueous Leaf Extract of Three Plant Species in North Cameroon

“…These insects reduce the photosynthetic potential of the plants, the quality of the seed and negatively affect yield. Many animal organisms such as bacteria and predators can protect plants against pests [9,10] while several useful insects facilitate the pollination [11]. More than 70% of agricultural production would suffer colossal on-farm and post-harvest losses without proactive and preventive measures [12].…”