Incidence And Control Of The Main Rice Diseases In Fang Qiang Farm

Jiangsu Fangqiang Farm,mainly engaged in crop production including rotation of rice and wheat,has an area of rice planting about 3 000 ha per year.Agricultural planting is the most important income for the farm while the quality of rice production has a significant effect on the economic benefits of the whole farm.In recent years,the damage caused by rice diseases has increased year by year.Among these diseases,sheath blight and blast were the two most serious diseases which generally result in a reduction of output from 5%to 10%and even to 30%sometimes.At present,there were four high-quality rice production bases and one organic rice production base in the farm.Taking many factors into consideration,such as the yield,cost,quality of the agriculture production and environmental protection,sustainable development of agriculture and so on,the farm is urgently required a comparatively mature green prevention and control technology for main rice diseases.Based on years of field research and data analysis,we found that whether rice sheath blight would be epidemic or not was mainly determined by the planting technology including rice population controlling,nitrogen fertilizer application rates and the management of fertilizer and water.The second factor is the resistance of culvivars.To a certanin degree,resistance of cultivars determines the severity of rice sheath blight.Among the cultivars planted in the Fangqiang Farm,Guangcan No.1 was the cultivar with the most seriously disease which was with an average diseased plant rate of 3.4%while Yanjing No.5,the cultivar with the lowest disease rate,was with an average diseased plant rate of 0.5%.Climate condition was the most important factor for the epidemic of rice blast.Because of the rapid variation of the pathogens,it is difficult to acquire a rice cultivar with broad-spectrum resistance in production.The temperature and rainfall between July and September,especially in early September,have direct effect on the epidemic degree of rice blast.Under suitable temperature,rainfall has a positive correlation with the severity of disease.In recent years,the diseased plant rate of rice blast in Fangqiang Farm was the highest in 2015 because of the lower temperature,less sunshine and more rainfall.In order to improve the quality of crops,high efficien,low toxicity,low residue and environment friendly fungicide,especially some biocontrol fungicide,should be applied in our farmto control the diseases.At the same time,advanced fungicide application technology should be used to reduce the loss in the fungicide application process,improve the control effect and reduce environment pollution.In this paper,the field efficacy of biogenic agents and their mixtures on controlling rice main diseases was determined.Results showed that the biogenic agents and their mixtures,purchased from the market,have the similar effect to that of the common chemical fungicide on controlling rice sheath blight and rice blast.Therefore,we think that the biological agents could replace the common chemical agents in the field.Under the condition of using the same fungicide,the control effect of plant protection UAV was slightly better than that of traditional stretcher-type mobile sprayer on rice diseases.