| Harmonia axyridis (Pallas) is subordinated to Coleoptera, Coccinellidae. It is one of important predatory natural enemies in agriculture and forestry systems. The ladybird preys on many pests, such as aphides, plant lice and mites. Due to long adult longevity and oviposition duration, large number of eggs laid, high fecundity, adaptability, many generations and large appetite, Harmonia axyridis (Pallas) is a kind of important predators on extractive industry. In this paper, effects of temperature on development of Harmonia axyridis and vitellogenesis on different diets were investigated.Developmental duration, the number of eggs laid and other physiological index were investigated at 15, 20, 25, 30 and 35℃, and constructed the life tables. And the characteristics of vitellin, vitellogenesis and effects of different diets on vitellogenesis were studied using PAGE , immunological techniques and coomassie brillant blue G-250 dye binding. In order to explore the optimal temperature of keeping the ladybeetle and their suitable artificial diet. Further theoretical guide for rearing and using them.The effects of temperature on development of Harmonia axyridis (Pallas) were studied. And the results indicated that developmental rate increased with the temperature increasing from 15 to 30℃, the duration of the generation were 65.5, 33.9, 23.0和22.4 d. Undering 35℃eggs could not hatch, and larva couldnot complete the generations.The threshold temperatures and the effective accumulated temperatures required for whole generation were 8.54℃and 432.61 degree-days. The lifespan was shortened with the temperature increasing and there was no apparent difference between the longevity of male and female adults. The longest lifespan of female was 79.4 days at 20℃, while the shortest was 39.5 days at 30℃. From 15 to 30℃, the number of eggs laid per female were 626.0, 1150.7, 2193.0 and 1079.7, while the oviposition were 47, 63, 64 and 32d. But ladybeetles couldnot lay eggs at 35℃. The highest survival rate was 86.1 % at 25℃and during 25℃to 30℃there were higher innate capacity of increase and index of population trend. In summary, 25℃was the best temperature for development and eggs laid of Harmonia axyridis (Pallas) than the other.The characterization of vitellin was carried out by PAGE and immunological techniques. The results indicated that we could gain 20 mg vitellin from 1g eggs. The immunological experiments results indicated that there was no vitellogenin in the hemolymph of males, and as other mature nonmamalian vertebrates, the vitellogenin of Harmonia axyridis (Pallas) only existed in hemolymph of females. In addition, there was no vitellogenin occurred in hemolymph of larvae and pupa shown that it synthesized vitellogenin after eclosion.The study of contents of protein suggested that the weight of ovary of the ladybeetles feeding on Chaitophorus populeti (Panzer) increased on the fourth day after eclosion, and became heavier than fat body on the sixth day. Only very few ladybeetles which feeding on artificial diets laid eggs, and weights of ovary and fat body of most of them increased to a certain number. When the ladybeetles became mature, the weights of ovary was no longer rising, and lighter than fat body. The results showed that there was no materials deposited in the ovary and the artificial diets couldnot meet the needs of Harmonia axyridis.On the third day after eclosion, a few of vitellogenin discovered in fat body, while there was no vitellogenin in ovary and hemolymph. And then vitellogenin detected in ovary and hemolymph, the peak of vitellogenin in fat body was followed by the peak in ovary. Suggested that the vitellogenin was synthesized by fat body, and then secreted into the hemolymph, at last transferred to ovary.
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