| In the recent years rice stripe disease caused by Rice stripe virus (RSV) has broken out in china and caused great decreases to rice yields. The most economical and effective way for controlling the disease is to culture resistant varieties. But little has been known about the resistance mechanism of rice by now. So further studies on the resistance mechanism should be carried out, which will be very important both in theory and practice.In this study, the resisitance of 50 rice varieties from Jiangsu, Fujian, Yunnan, Zhejiang, Liaoning, Sichuan, etc. was identified. The results show that 40% rice varieties are high susceptible, 34% rice varieties are middle susceptible, and middle resistant rice varieties only make up 26%. To make further researches on the resistance mechanism, Wuyujing-3 and Taizhong-1 were chosen as the typical susceptible variety and resistant variety respectively for the experiment about the interaction between rice and RSV (Small brown planthopper).With different inoculation process, the statistics of the incidence of RSV in the field show that resistance not only includes resistance to RSV, but also resistance to small brown planthopper. 1) Resistance to RSV. An experiment was carried out by continuous recording the physiologic index (chlorophyll, malondialdehyde, peroxidase, phenylalanineammonialyase) of rice after infected by RSV and the content of RSV. Adding the external symptom changes, a Pilot discuss on the resistance mechanism was made; 2) Resistance to small brown planthopper. 3 aspects were concerned: resistance (from narrow sense), tolerance and appetencies. The results show that all 3 aspects have something to do with the resistance.By directional artificial induced mutation and RSV CP and NSvc4 sequence analyzed, 2 variable sites (795 and 860) in CP gene probably associated with rice resistance were founded, and no variable sites probably associated with rice resistance were found in NSvc4 gene.With different inoculation process, the statistics of the incidence of RSV and the rate of carrying RSV for small brown planthopper in the field show that acquiring of RSV is the bottleneck in the spreading of RSV. Resistant varieties also have bottle neck effect on acquiring of RSV and spreading of RSV. The statistics also show that it is the main way for RSV to live through the winter in the body of small brown planthopper.This is only a first step on the road to understand the resistance of rice, which is too huge to do for an individual. The purpose of the thesis is just to help the subsequent researchers in physiology, plant pathology, plant virus, etc. to make further research on post-genomics, proteomics, metabolomics, etc. and finally understand the resistance mechanism.
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