Approaches Of The Extracts From Sophora Alopecuroids And The Relative Control Pesticides Against Tomato And Cucumber Root-knot Nematode

Recently more attention has been paid on products of natural plants which play a important role on encouraging studies of recent to organic synthetic pesticides which is a serious threat to the environment such as resistance, residue and resurgence. In this paper the affection of seven biological source nematicides including extracts from Sophora alopecuroids and the relative control pesticides against the root-knot nematode Meloidogyne spp., and their application technology were studied in the pot trial and in the field in Jining, Shangdong province. Meanwhile, the effect experiments of different soil characters and moisture on the controlling effects against the root-knot nematode were also approached in the paper. The results could be summarized as follows:1. The extracts from Sophora alopecuroids were collected by methyl acohol and water ,and the content of the major alkaloids were determined.2. Among the tested preparations, the joint- agent of the extracts and avermectin showed the best control effect against Meloidogyne spp., as well as the another similar preparations with the form of granule named Jinwei Miexian. The descending sequence of the effect as follows: 6% S. alopecuroids mixed avermectin microemulsion>5% Jinwei Miexian granular preparation> 1.8% avermectin emulsifiable concentrate> 3% sazofos granular preparation> the extracts from S. alopecuroids. It indicated that the extracts mixed with avermectin have a better control effect, in addition, which can also improve the growth situation of the plants obviously.3. Three kinds of preparation screened were tested in the field in order to select the most appropriate applying technology. Different kinds of vegetables were also tested in the soil of different characters, and found that 1000-2000 folds diluent of 6% S.alopecuroids mixed avermectin microemulsion (720g (a.i.) / ha) with the douching method, as well as 5%Jinwei Miexian granular preparation (3000g (a.i.) / ha) with hole employing way after being mixed with soil, had the best effect in the loam infected by root-knot nematode seriously at the rearing period. The contents of 6% S.alopecuroids mixed avermectin microemulsion and 5% Jinwei Miexian ought to be decreased 540 g (a.i.) /ha and 2250 g (a.i.) / ha respectively in the infected slightly soil by the root-knot nematode. The preparation contents should be increased appropriately in sandy soil, and decreased properly in the clay.4. Inspecting trial of the suitable applying technology was operated in the field, and found that two months later the preparation should be used again after the first application to get the highest products, when applied to the vegetables with long growth period.5. Soil characters and different moisture had obvious influence on the control effect when the biological source nematicides were used in the field . The descending effect sequence of the same preparation concentrates was clay>loam>sandy soil. Controlling effect could be improved slightly with increasing of the moisture, and S. alopecuroids mixed avermectin had the best effect when the relative humidity was around 60%.