Mapping The Broad Brown Planthopper Resistance Genes Derived From Common Wild Rice, Oryza Rufipogon Griff

The brown planthopper (BPH)(Nilaparvata lugens Stal) is one of the most serious insect pests of rice in the world and in china. Breeding resistance varieties is the most economic and effective way to control the pest. In present study, the resistance genes derived from Oryza rufipogon Griff were mapped on the basic of the study that had been found two new genes with broad and high resistance against BPH.Broad and high resistance genes against brown planthopper (BPH)(Nilaparvata lugens Stal) derived from resource "2183" of Guangxi common wild rice, Oryza rufipogon Griff were tagged and mapped in this study. Genetic homozygous resistance material, "2183 "was obtained by anther culture technique and used to cross with TN1, a susceptible rice variety. Testcross was made and the TC₁F₂ population was used to evaluate its resistance to the BPH biotype 2. Two hundred and thirty nine pairs of polymorphic rice SSR markers were employed for genome-wise screening. Genetic map was maded by used of Mapmaker /Exp3.0. A tentative resistance gene bphl8(t) was mapped in the middle part of long arm of chromosome 4, 6.0cM map distance to SSR markerRM273, 12.4cM to RM6506, and 10.4cM to RM252. The gene was mapped between RM273 and RM6506. The bphl8(t) was not allelic with all known BPH resistance genes in the same chromosome 4 and was possibly a new resistance gene.Another tentative resistance gene bph19(t) was mapped near the end of the long arm of chromosome 12, 16.7cM map distance to SSR marker RM17, but its exact location remained unknown. The bph19(t) was found not allelic with BPH known resistance genes Bph1, bph2, Bph9(t) and BphlO(t) in the same chromosome 12 and was possibly another new resistance gene. Interaction of the two resistance genes in the "2183 "may be the reason for its broad and high resistance against the BPH. As it belonged to the same AA genome with cultivated rice, the common wild rice derived BPH resistant source would be important for its resistance genes easily transferred and used for rice breeding.