Abstract:

The study aims to understand the effects of choline chloride on the biological characteristics of Coccinella septempunctata, and screen the optimal dose of choline chloride in artificial diet for feeding ladybird. Five groups were set up with different doses of choline chloride (A, B, C, D, E represent doses of 50, 100, 150, 200, 250 mg/100g, respectively), and fed with soybean aphid (1-dayaphids + 3-day feed), C. septempunctata were fed with artificial diet without choline chloride as control group (CK). The spawning quantity, feeding, mating, hatching and survival rate of each treatment were recorded. In the first 20 days, the average egg production of A, B, C, D, E and CK were (286.30±35.14), (342.4±26.79), (242.65±25.38), (241.90±32.24), (240.45±24.34) and (230.00±23.00) eggs per female, respectively, and the average egg production of group B was significantly higher than those of other groups. There was no significant difference between other groups. There were no significant differences in feeding frequency, mating frequency, adult survival rate and egg hatching rate among different treatments. The combination of artificial diet with 100 mg/100 g choline chloride and bean aphid significantly increased the egg production of ladybird at 20 days of age, but had no effect on other biological indexes.

Key words: choline chloride, Coccinella septempunctata, aphid, artificial feed, biological control, egg production, biological indexes