Harm And Disease-controlling Strategy Of Rice Stripe Blight In Shanghai Farm

Rice stripe blight is a virus disease introduced mainly by Laodelphax striatellus Fallen. Rice stripe virus is a RNA virus and one of Tenuivirus members. Rice stripe virus can intrude and infect several cereal plants, and reproduce and spread permanently in host insect (Laodelphax striatellus Fallen) and plants。We have highly regarded the occurrence and development of Laodelphax striatellus Fallen since we found Rice stripe blight in the Shanghai farm in 2001. Rice stripe blight occur only bits and pieces and didn't result in obvious harm from 2001 to 2003, and quantity of Laodelphax striatellus Fallen was very low and only in part place it was more serious. Amount of Laodelphax striatellus Fallen has been increased and rate of diseased rice has been developed since 2004. Along with increase of infecting area and diseased plant rate year after year, the harm of rice stripe blight reached peak in 2005 and resulted in serious rice yield reduction. Yield of Wuyujing series cultivars was reduced about the 50 percent and there was almost no any output in some farmland. Thus, prevention and cure for rice stripe blight has become an important object in Shanghai farm.I have engaged in the research of rice stripe blight control for many years in Shanghai farm and found some problems: though there were some reports of research on rice stripe blight resistance, strategy of prevention and cure for the disease has been face to farmer mainly, while geographical location, cultivars and cultivation system adopted on the Farm all affect the effect of control. On the other hand, our Farm has paid attention to the chemical prevention and cure for rice stripe blight and ignored other measures. As for the chemical prevention and cure, phenomenon of drug-resistance and bad effect of prevention and cure existed usually.Aim at the influence factors about special field, cultivation system and cultivating level of rice in Shanghai farm, I studied characters of rice stripe blight occurrence on the Farm, investigated the disease resistance level and yield lose rate of different rice cultivars planted on the Farm, and made the suggestion about a synthetical control strategy for the disease in priority to adopt rice cultivars with resistance to the disease. Through investigation for the actuality of plant protection in Shanghai Farm and the examination of medicament for the disease, I gave an advice about the best chemical controlling method for the disease.