septempunctata under different climatic conditions, notably temperature and different prey densities.Įffects of temperature on C. Development of biological control for cotton aphid requires insight into the bionomics of C. Biological control of the cotton aphid is a priority for integrated cotton pest management to avoid early season application of insecticides, thus laying a foundation for biological control throughout the season ( Xia et al. SEVENSPOTTED LADY BEETLE, Coccinella septempunctata L., is a key predator of cotton aphid ( Aphis gossypii Glover) at the seedling stage of cotton ( Gossypium hirsutum L.) in the North China cotton region ( Beijing University 1984). A 2-fold increase in prey density brought about a 2-fold increase in lifetime oviposition and mean oviposition rate.Ĭoccinella septempunctata, Aphis gossypii, bionomics, temperature, prey density Introduction Over the range of prey densities tested, a 3.5-fold increase in prey density resulted in a 2-fold reduction in larval development time and a 3-fold increase in larval survival.
The thermal constant was 42.0, 103.7, 63.6, and 302.9 DD for eggs, larvae, pupae, and adults, respectively. Threshold temperatures for development of the respective stages ranged from 10.9 to 13.9☌, with 12.6☌ for the entire life span. Oviposition was greatest at 25☌, with a lifetime oviposition of 287.4 eggs per female and a mean oviposition rate during the reproductive period of 22.4 eggs per female per day. Survival from egg to adult was highest at 25☌ (47%). septempunctata developed most rapidly at 35☌, with a preimaginal period of 10.8 d. Relationships of life cycle parameters with abiotic and biotic factors were described by mathematical equations. The 2nd experiment addressed the effect of food quantity on the beetle’s bionomics at 25☌. septempunctata bionomics supplied with unlimited food. The 1st experiment addressed the effect of temperature (15, 20, 25, 30, and 35 ± 0.5☌) on C. feeding on Aphis gossypii Glover on Gossypium hirsutum L. Life history parameters of Coccinella septempunctata L.
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