Studies Of Biological Pesticide Vertrine Against Cabbage Aphids And Its Applications

This paper studied the biological pesticides. Biological pesticides are environment-friendly pesticides. Developing biological pesticides could reduce the use of chemical pesticides which are the main source of contaminations in the agricultural environments. At the same time, the development of biological pesticide will improve agro-products'market value, and increase farmers' income and prompt rural prosperity.Vertrine,extracted from plants, has contact and stomach toxicity and similar control ranges with nicotine. Having low toxicity to human and livestocks and low residue in environments, vertrine is paid close attentions nowadays. In order to apply prospective biological pesticide vertrine properly in pest control, we assayed the biological activities of vertrine (0.5%vertrine WP) against cabbage aphids in laboratory and conducted a series of field trials in Henan, Shandong and Anhui province to assay vertrine's control effects against cabbage aphids. We also evaluated and compared the control effects of Kusanjian and imidacloprid, a common chemical pesticide against cabbage aphids, with vertrine.The immersion method was used to test vertrine's toxicity against cabbage aphids in lab. The results showed the mortality of aphids were 10.6%, 22.5%, 32.1%, 50.3%, 73.9% and 90.5% respectively to our testing conditions. The LC50 is 3.1821μg/mL and LC90 was 18.8869μg/mL.Field trials indicated the vertrine was not satisfied in the control of cabbage aphids in short time, but had satisfied control effects against cabbage aphids in 3 days and after. The control efficiency could reach 80% and over. The field trials also indicated 0.5% Vertrine WP in 100-125g/mu (i.e. 7.5-9.31g (a.i)/hm~2) was the optimal dosage to control cabbage aphids.