Molecular mapping of the blast resistance gene Pi49 in the durably resistant rice cultivar Mowanggu
Molecular mapping of the blast resistance gene Pi49 in the durably resistant rice cultivar Mowanggu
复制标题
长效水稻品种磨王谷抗稻瘟病基因Pi49的分子定位
DOI：
10.1007/s10681-012-0829-3
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发表时间：
2013-07-01
期刊：
影响因子：
1.9
通讯作者：
Dai, Liangying
中科院分区：
文献类型：
--
作者：
Sun, Pingyong;Liu, Jinling;Dai, Liangying
稻瘟病是水稻最具破坏性的真菌病害，由稻瘟病菌引起。毛王谷是中国云南省的一个地方粳稻品种，对该病菌具有广谱抗性。为了鉴定毛旺谷的抗性基因，我们从毛旺谷与高敏感籼稻CO39杂交获得F2群体和280个F8重组自交系（RILs）。利用280个ril，构建了包含12条染色体上145个SSR和单特征多态性标记的连锁图谱。在生长室和天然稻瘟病苗圃中对F2和F8群体的抗性评价表明，水稻稻瘟病抗性由单一显性基因控制。在2、3、6、8、9和12号染色体上分别定位了9个数量性状位点，对表型变异的贡献率在3.03 ~ 6.18%之间。抗性优势基因Pi49定位在第11染色体上，与SSR标记K10和K134的遗传距离分别为1.01和1.89 cM。在Nipponbare基因组中，K10和K134的物理距离约为181 kb。在生长室（用单个胚分离株接种植株）中，Pi49基因是疾病严重程度的主要表型变异，在胚室中，Pi49基因也是疾病严重程度、病变数量、病叶面积和病变大小的大部分表型变异的原因。我们的研究不仅通过标记辅助选择鉴定出了Pi49向水稻优良品种渗入的紧密连锁标记，而且为新的抗性基因的图谱克隆提供了一个起点。
Rice blast, caused by the fungus Magnaporthe oryzae, is the most devastating fungal disease of rice. Mowanggu, a local japonica cultivar in Yunnan Province, China, confers broad-spectrum resistance to this pathogen. To identify the resistance gene(s) in Mowanggu, we obtained an F2 population and 280 F8 recombinant inbred lines (RILs) from a cross between Mowanggu and CO39, a highly susceptible indica cultivar. A linkage map with 145 simple sequence repeat (SSR) and single feature polymorphism markers over 12 chromosomes was constructed using the 280 RILs. The resistance evaluation of the F2 and F8 populations in both the growth chamber and in a natural rice blast nursery showed that a single dominant gene controls blast resistance in Mowanggu. Moreover, nine quantitative trait loci, which were responsible for different partial resistance components, were mapped on chromosomes 2, 3, 6, 8, 9, and 12, making contributions to the phenotypic variation ranging from 3.03 to 6.18 %. The dominant resistance gene, designated Pi49, was mapped on chromosome 11 with genetic distance of 1.01 and 1.89 cM from SSR markers K10 and K134, respectively. The physical distance between K10 and K134 is about 181 kb in the Nipponbare genome. The Pi49 gene accounted for the major phenotypic variation of disease severity in the growth chamber (where plants were inoculated with single blast isolates) and also accounted for most of the phenotypic variance of disease severity, lesion number, diseased leaf area, and lesion size in the blast nursery. Our study not only identified tightly linked markers for introgression of Pi49 into elite rice cultivars via marker-aided selection but also provides a starting point for map-based cloning of the new resistance gene.