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Rice blast is the most widely distributed, and the most serious harm to the world rice diseases. Both in the world and in our country, solve the rice blast problem has been to safeguard the sustainable production of rice research priorities. Magnaporthe reason why the perennial incidence and prevalence, on the one hand the other hand, because of the production on the lack of broad-spectrum durable resistance rice blast fungus is easily mutate the pathogenic species multiply rapidly lead cultivars in the short-term loss of resistance; The disease improved varieties. Therefore, the discovery and use of broad-spectrum anti-source, and to cultivate a broad spectrum of resistant varieties by the polymerization of the broad-spectrum resistance gene, has been considered to be the most effective way to control rice blast. In Indica 9311 for its high-quality, multi-resistant, high-yielding properties known. 352 rice blast strains, this study by vaccination stems from different rice growing regions confirmed to have a broader spectrum of anti-9311 pairs of our country, especially japonica strains of rice blast, as rice blast excellent anti source. 9311 (paternal) and a general sense of Magnaporthe varieties LTH Valley (LTH, female parent) hybrid F2 the F3 groups for the experimental material, by Inoculation and genetic analysis found 9311 pairs indica District of strain 001-99 - and japonica District strains 99-26-2 resistance is governed by a single dominant gene control, and the two genes are inherited independently, tentatively named Pi93-1 (t) and Pi93-2 (t). By molecular marker gene mapping method combined with the analysis of the BSA-RCA 1698 strains 001-99-1 extreme susceptible F2 plants mapping population Pi93-1 (t) is positioned on the short arm of chromosome 11 in central 0.22 cM (143 kb) segment distance on both sides of the Indel labeled 11-B14 and 11-E13 for 0.17cM and 0.05cM three markers 11-H2 ,11-H4 and 11-H6 were isolated. The Indel mark for another 539 strains 99-26-2 extreme susceptible F2 plants do figure groups, Pi93-2 (t) is located in the 12 chromosomes Central 0.55 cM segment from both sides 12-6 and 12-G8 were 0.18 cM and 0.37 cM, with mark RM27990, and Indel12-5, were isolated. Rice varieties and a single isogenic lines, carrying the target gene through the use of differential strain was inoculated and Pi93-1 (t), Pi93-2 (t) and its neighboring known resistance genes for linkage analysis, to confirm the Pi93-1 (t) is a new blast resistance gene; excluded Pi93-2 (t) for the known genes Pita is, the Pita is-2, Pi12 (t), Pi19 (t), PI20 (t), the possibility of Pi39 (t), Pi41 (t) in 9311 in the same gene cluster. According to the 9311 sequence, Orygenesdb, Gramene database 2 resistance gene target segments within the gene prediction and analysis, initially identified candidate genes for three NBS-LRR gene Pi93-1 (t), an NBS -LRR class genes Pi93-2 (t) of the candidate genes.
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