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Poster: Biology & Disease Mgmt: Genetics of Resistance


Analysis of Resistance to Blast Isolates and Mapping of Rice Blast Resistance Gene in T2
Q. YANG (1), D. Sun (2), G. Chen (2), J. Zhang (2), D. Zhou (3), X. Zhu (2), H. Wang (3), Z. Chen (3) (1) Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, China; (2) Institute of Plant Protection, Guangdong Academy of Agricultura

To understand the genetic mechanisms of space-induced rice mutants’ resistance to blast, T2, an indica rice mutant from TaiHang68, was subjected to resistance spectrum using 39 blast isolates collected from Guangdong Province, China along with main cultivars from Guangdong province. The results showed that T2 conferred broader resistance spectrum than most of main cultivars from Guangdong province. Genetic analysis and gene mapping were also applied in this study. Isolate GD0193 was used for inoculating a population of F2 derived from the cross between T2 and highly susceptible variety LTH. The results showed that the segregation of resistant (R) and susceptible (S) progenies matched a 3:1 ratio in the F2 population (1585R:537S, χ2= o.77, P>0.75), indicating that this R gene was controlled by a single dominant gene, temporarily designed as PiTH gene. The R gene was mapped between T5 (1.4 cM) and K10 (0.29 cM) at chromosome 11 using SSR and InDel markers, and it was co-segregating with marker K7. PiTH may be a novel resistance gene in the Pik cluster, which contributes greatly to the blast resistance of T2. Thus, T2 could be used as a new germplasm to facilitate rice blast resistance breeding.