Studies On The Occurrence Regularity And Control Technique Of Sitona Ophtalmicus Desbrochers In Astragalus

Astragalus Markou disease is important diseases in Astragalus mongolius，famous for the pock grain size of the pit (hole) like the callus in Astragalus surface.Because the occurred of Markou disease，resulting in the Astragalus productiondecreased year by year，the finished product quality constantly decline，commodityprices also fell affected by Markou disease，seriously affected the enthusiasm offarmers to plant，inhibit the development of Astragalus industry，so the production isan urgent need to solve this problem.The cause of Markou disease has many opinionsin the industry，such as root rot pathogenic、nematophila statement、fusarium wilt.Inorder to clear the real causes of the Markou disease，and to provide effectiveprevention path ways for the production，we implement this study in2010-2012.The study made clear that the root rot fungus and nematodes can not causeMarkou disease，make sure the Sitona ophtalmicus Desbrochers is pathogenic pests ofmarkou disease.We get the best way to prevention Markou disease by the chemical control:soiltreated with5%carbosulfan GR (45kg/hm~2) before transplanting and one times ofirrigating roots treated by15%emamectin· chlorpyrifos EC(30kg/hm~2)in June.Control efficacy tests in fields indicated that the control effect was87.51%and thedamnification of output could be redeemed92.14%.This method does not produce asignificant effect on astragalus seedling emergence rate and has no phytotoxicity.Determination of pesticide residues shows that:The pesticide residues hazards bysoil treated with5%carbosulfan GR before transplanting and one times of irrigatingroots treated by15%emamectin·chlorpyrifos EC are in the state’s standards，we makesure the way can be widely used in the production.