Research Of Monitoring Forecast And Integrated Prevention To The Main Diseases And Insect Pests Of Cowpea (Vigna Unguiculata (L.) Walp.) In Lishui Area

Cowpea(Vigna unguiculata L.Walp) is a leguminous crop that is widely cultivated in South China.Now,the cultivation area of cowpea has reached to 100 000 hm~2,and the production value is 300 000 000 yuan per year in Liandu District,Lishui City,Zhejiang Province,which is the largest production site of Cowpea in East China.Planting cowpea has already become the main agricultural industry and the main income to most farmers.With the expansion of cultivation area,diseases and insect pests of cowpea prevailed seriously day by day.Due to the damage caused by diseases and insect pests, the yield reduced by 20～30%in common year,or 50%when worse off,or even total destruction.Therefore,diseases and insect pests have already been the main factor restricting the high and stable yield of cowpea and the supply in market.Controlling diseases and insect pests has become a focus in the non-contaminanted production of cowpea.According to the actual situation of cowpea production in Lishui area,the technologies of forecasting and the skills of integrated control to the main diseases and insect pests of cowpea were studied in our research.The technology system of integrated prevention to the main diseases and insect pests,which is consistent with the non-contaminanted cowpea production in Lishui area,were established and popularized in large area.And it provided a theoretical basis and technical guidance for the safety production of cowpea.The main contents of this research were as follows:1.The occurrence and propagation rules of main pests of cowpea in Lishui district were studied.The main occurring characteristics of Spodoptera litra(Fabricius) in Lishui area are as follows:the occurrence is not serious at the first generation,grave damage happens from 2 to 4 generation,always harms for a long time,has a huge propagation coefficient,and the occurrence status is complex.The peak damage period of Laphygma exigua Hubner is July to September,while Maruca testulalis Geyer is July to August. Fusarium Solani(Mare) is easy to happen in April to October,the incidence peak of Spring cowpea and Autumn cowpea is respectively in April and September.It could happen during the whole growing season of Summer cowpea.When the ground temperature rose from 25℃to 28℃,Fusarium oxysporum Sch1.caused serious damage. Under the high temperature condition,Uromyces vignae Barclay is easily to epidemic. The optimum temperature is about 25℃,and it always happens seriously under high rain and humidity condition.2.The technologies of forecasting of the main diseases and insect pests in Lishui area were studied.The peak of adults Spodoptera litra(Fabricius) can be exactly monitored by using sex pheromone.It would provide a basis for the forecastion of larva Spodoptera litra(Fabricius).Thus,sex pheromone,can be used as an observation technology for forecasting and predicting Spodoptera litra(Fabricius).The occurring stages of Laphygma exigua Hübner are forecasted by growing period.It will be more precise when analysed and revised by additional black light lamp lured status.The error of the forecastion was within 1～2 d,so it can be applied to forecasting.Comprehensive studies about biological characteristic of Maruca testulalis Geyer was carried out.The life cycle of Maruca testulalis Geyer in Lishui area was clearly identified.Some peaks in late June,mid to late July,mid August,mid September and mid October were found respectively.And the generations occurred undulatingly.While,there was no obvious distinction between the damage degrees of each generation.3.The technologies of integrated control of the main diseases and insect pests of cowpea in Lishui area were studied.According to the occurrence rules of main pest propagation,effectiveness of agricultural control,biological control,physical control and chemical control on controlling the diseases and insect pests of cowpea were studied.The technology system of integrated prevention to the diseases and insect pests,which was consistent with the non-contaminated cowpea production in Lishui area,was established. And then these skills are popularized and applied to production.