| Cnaphalocrocis medinalis (Guenee) and Sogatella furcifera (Horvath) are two main migrate pests of the rice. In recent years, the pests have happened more heavily, which is endangering the rice product and food safety and has become the biggest problem of controlling the rice pests.What the thesis studied are as follow:occurrence rule of Cnaphalocrocis medinalis(Guenee) and Sogatella furcifera (Horvath) in Chongqing, forecast and prediction of Cnaphalocrocis medinalis (Guenee), the influence of pesticides affecting to Sogatella furcifera (Horvath) and its enemies and the effect enemies to Sogatella furcifera (Horvath) and Cnaphalocrocis medinalis(Guenee). The results are as follow:1 Occurrence rule of Cnaphalocrocis medinalis (Guenee) and Sogatella furcifera (Horvath) in ChongqingThrough the pest survey datas, we ensure that the reason for the eruption of Cnaphalocrocis Medinalis (Guenee)and Sogatella furcifera (Horvath) is the big number of migrating pest and proper weather condition. Wuling mountain path and Dalou mountain path are the main immigration paths of two pest, and Xiushan acts as the first station of Wuling mountain path, which influnened the occurrent of the pest in Chongqing directly.Dalou mountain path is another imporant path besides Wuling mountain path, and the pest are mainly from Yunnan, Guizhou and so on, but the two paths are overlapped.2 Forecast and prediction of Cnaphalocrocis medinalis(Guenee) in Fuling,ChongqingAssemble incidence of Cnaphalocrocis Medinalis (Guenee) larvae 3 in Chongqing Fuling in 1987-2006 by time serises, build fuzzy model by Fuzzy, and investigat and forcast incidence of Cnaphalocrocis Medinalis (Guenee) larvae 3 in Chongqing Fuling from 1987 to 2006. The results reflect that fitting rate of 20 years is to 80%. Forcasting of 2007-2009 pest situation,the results of 2007and 2008 are the same with the facts. The way does not need to consider environmental and migration factors, and evolves only features about incidence of Cnaphalocrocis Medinalis (Guenee). So it is a much easier way.3 Resistance of different rices to Cnaphalocrocis medinalis(Guenee) and Sogatella furcifera (Horvath)The rolling quantities in four rice species display a marked difference. Rolling quantity of dominant variety-yuyou 12 is the most,and the resistance is lower. Among the rice species,A232,09DF279 and DF2 from Sichuan agricutle academy, the resistance of DF2 and A232 were higher than 09DF279.In the evaluation on resistance level ofA232,09DF279,DF2 and Chongqing-yuyou 12 by man-handle, the result shows that the resistance level of 09DF279 is higher than others, yuyou 12 is the main variety in Chongqing, the resistance level of which is lower, and it is a susceptible species.infection pest. DF2 has the higher resistance to the pest than others, which is worth further study of resistance mechanism and heredity.4 The survey of pest enemies in Fuling and the influence of different pesticides to the Cnaphalocrocis Medinalis(Guenee) and rice spiderWe have investigated enemies species of Cnaphalocrocis Medinalis(Guenee) in Fuling. The ricefield spider is the main enemy of Cnaphalocrocis Medinalis (Guenee)and Sogatella furcifera(Horvath) and Tetragnatha japonica Boes.et Str is the dominant enemy species which is over 40 percent of spiders. A Tetragnatha japonica Boes.et Str predates 6-7 Sogatella furcifera (Horvath) and 2-3 Cnaphalocrocis Medinalis(Guenee) in 36 hours.The effects of three pesticides to Sogatella furcifera (Horvath) show that the effects of Chlorpyrifos and buprofezin are better than that of Chlorantraniliprole, and that the persistence of buprofezin is better. The result shows that in controlling Sogatella furcifera (Horvath), the control efficiency of Chlorpyrifos is higer than Chlorantraniliprole and buprofezin,and the decrease rates of decease are 40.32% and 32.80% respectively. Chlorantraniliprole is less lethal than chlorpyrifos and buprofezin, which is only 7.28%.
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