Screening And Molecular Detection Of Rice Cultivars For Resistant To Rice Black Streaked Dwarf Virus

Rice(Oryza sativa L.), commonly known as one of the major food crops in China, plays a very important role in national economy. In recent years, Rice black streaked dwarf disease(RBSDD) have done seriously harm to cause great loss of production in the south japonica rice region of China, which was caused by Rice black streaked dwarf virus(RBSDV). Due to the lack of natural resistance genes in rice, resistance evaluation of the main varieties and development of RBSDV-resistant transgenic plants were promoted to be conducted. Moreover, research showed that the technology of RNA interference(RNAi) was one of the most effective methods to obtain transgenic disease-resistant plants. Compared with traditional methods of breeding methods, transgenic plants have many advantages such as shorter cycle, controllable agronomic traits, etc..66 main rice varieties, which were largely cultivated in China, and advanced lines were evaluated on disease resistance by natural inoculation in Kaifeng city, Henan province where was the area of Rice black streaked dwarf disease epidemic seriously. The disease incidence of rice was range from 13.01% to 93.7% in field. Among the rice varieties, the disease incidence of Liandao 9805 was the lowest(13.0%), and 93.7% was the highest percentage which was the disease incidence of Yan 1403. As the susceptible control variety, the disease incidence of Huaidao 5 was 89.5%. In conclusion, Liandao9805 is the only highly resistance variety; 12 varieties have the moderate resistance(Liangyou 1129, Y Liangyou 3399, Ningjing 4, Daliang 207, Xudao 7, Yangliangyou 6, X008, Zhongdao 1, Chaojidao, Shengdao 15, Yuanhandao 3, and Shendao 301). The results in this study can provide scientific basis for cultivation and studies on resistance genes.In this study, field resistance screening and molecular identification methods were used on 14 transgenic plants of T4 progeny and 8 transgenic plants of T5 progeny in the areas of Rice black streaked dwarf disease epidemic seriously and frequently. In conclusion, 8 positive lines were got which had not hygromycin selection marker gene. Among the 8 positive lines, there was one highly resistance line(RB201), two moderate resistance lines(RB101 and RB110) and five susceptible lines(RB85, RB104, RB134, RB143 and RB200, respectively).