The Relationship Between The Occurrence Of Rice Stripe Virus And Rice Varieties, As Well As Stripe Virus Detection And Control Technology Research

Rice strip virus was very popular in Jiangsu province and its nearby regions recent years, and brought huge loss to rice yield. One of the reasons of the population of the disease is lack of chemicals against the virus and resistant rice varieties against the virus. Four rice varieties, wujing 15, wuyunjing 7,yangfujing 7 and yangjing 9538, popularly used in Jiangsu province, were used in the research. The effects of the four rice varieties on the nymph development were tested. The results showed that the nymph development durations on wujing 15,wuyunjing 7,yangfujing 7 and yangjing 9538 were 17.30d,15.69d,21.14d and 20.87d, respectively, and that of yangfujing 7 and yangjing 9538 were lager than that of wujing 15,wuyunjing 7 significantly. It is indicated that wujing 15 and wuyunjing 7 are more susceptible to the nymph that yangfujing 7and yangjing 9538.The adults were transplanted to plants of wujing 15 and wuyunjing 7, and the relationship between density and components of rice yield were studied. The loss of yield is contacted with number of useful ear, percentage of ripened grains on wujing 15, and the linear regression equation between pest density and number of useful ear, percentage of ripened grains and yield were y=26.2457-0.6141x (r=-0.8737﹡),y=47.3477-0.7840x (r=-0.9353﹡﹡) and y=22.3846-0.6075x (r=-0.8546﹡), respectively;on wuyunjing 7 were y=24.0740-0.7460x ( r=-0.9760﹡﹡ ),y=62.6850-0.5315x(r=-0.8076) and y=28.3530-0.9085x (r=-0.9871﹡﹡ ), respectively. The correlation coefficient was significant. The control thresholds were estimated on different varieties. It was 16900/667㎡ and 11400 /667㎡ in wujing 15 and wuyunjing 7, respectively.The toxicities of some popularly used pesticides to the pest were tested in laboratory by the rice stem-dip method, and control efficacy of different insecticides were evaluated. RSV in the body of the pest was tested by DIBA. The rate with RSV of the older larva or adult of the over-winter generation,1st generation,2nd generation and 3rd generation from some regions were tested. The RSV in rice leaf was also tested by RT-PCR.The control effects of kinds of chemicals resistant to RSV on rice strip were screened. It was showed that Bingdukang of 75g/667㎡ and 100g/667㎡ has better control effect, and has very significant difference with others. Some pesticides with better controlling against the pest were also screened to control rice strip disease.