作者机构：
[郝明; 黄湘桂; 降好宇; Zeng G.; 肖应辉] Agronomy College, Hunan Agricultural University, Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Changsha, 410128, China
摘要：
Effective management of rice blast, caused by the fungus Magnaporthe oryzae, requires an understanding of the genetic architecture of the resistance to the disease in rice. Rice resistance varies with M. oryzae strains, and many quantitative trait loci (QTLs) affecting rice blast resistance have been mapped using different strains of M. oryzae from different areas. However, little is known about the genetic architecture of rice resistance against the M. oryzae population in Hunan Province, which is a main rice production area in South China. In this study, we used three isolates from Hunan Province and the rice diversity panel 1 to perform a genome-wide association study (GWAS) of blast resistance in rice. A total of 56 QTLs were identified. One of the QTLs is localized with the resistance gene Pik locus which confers resistance to all three isolates. Genomic sequence analysis of the resistant cultivars led to the identification of a new Pik allele, which we named Pikx. Yeast two-hybrid and co-immunoprecipitation assays between AvrPiks and Pikx confirmed that Pikx is a new allele at the Pik locus. Our GWAS has identified many new blast resistance QTLs. The identified new Pik allele Pikx will be useful for breeding cultivars with high resistance to blast in Hunan and other South China provinces. Further research on the relationship between AvrPiks and Pikx will provide new insights into the molecular mechanism of rice resistance to M. oryzae.
期刊：
International Journal of Agriculture and Biology,2018年20(3):554-560 ISSN：1560-8530
通讯作者：
Hu, Peisong
作者机构：
[Huang, Fenglin; Xiao, Yinghui; He, Jiwai; Wang, Jianlong; Hu, Peisong] Hunan Agr Univ, Coll Agron, Changsha 410128, Hunan, Peoples R China.;[Huang, Fenglin; Shao, Gaoneng; Wei, Xiangjin; He, Jiwai; Sheng, Zhonghua; Tang, Shaoqing; Hu, Peisong] China Natl Rice Res Inst, State Key Lab Rice Biol, Hangzhou 310006, Zhejiang, Peoples R China.;[Huang, Fenglin; Xia, Shengpin] Hunan Acad Agr Sci, Hunan Rice Res Inst, Changsha 410125, Hunan, Peoples R China.
通讯机构：
[Hu, Peisong] H;[Hu, Peisong] C;Hunan Agr Univ, Coll Agron, Changsha 410128, Hunan, Peoples R China.;China Natl Rice Res Inst, State Key Lab Rice Biol, Hangzhou 310006, Zhejiang, Peoples R China.
关键词：
Mapping;QTLs;Recombinant inbred lines;Rice;Trace metal element concentrations
摘要：
Trace metal element concentrations in rice (Oryza sativa L.) have great effects on the health of human being. In this study, QTLs for the concentrations of Cd, Cu, Fe, Mn and Zn in brown rice were identified using a recombinant inbred lines (RIL) population. A total of 22 QTLs for the concentrations of Cd, Cu, Fe, Mn and Zn in brown rice were identified with 204 recombinant inbred lines (RILs), including qCd5 for pot cultivation (PC) with Cd stress and paddy field cultivation (FC) trials in Hangzhou, 9 for PC trial only, and 13 for FC trial only. The phenotypic variance explained by a single QTL ranged as 4.6-9.9% and 2.8-10.4% in PC and FC trials, respectively. Among all QTLs, qCu4-2 had the largest single effect (10.4% of the phenotypic variance), qCu7 had the lowest single effect (2.8% of the phenotypic variance). The positive alleles (increasing trace metal element concentrations) at 16 QTLs except qCd2, qCu7, qFe7, qMn7, qZn1-1 and qZn4 were inherited from the female parent Zhenshan 97 B (ZS97B). These QTLs distributed on chromosomes 1, 2, 4, 5, 7, 8, 10 and 11. Six QTLs were clustered in 1, 4 and 7 chromosomal regions. Especially, qCd5 was a novel QTL regulated low Cd accumulation in rice. The identification of QTLs provides good candidates for fine mapping and cloning, and could be utilized to improve rice safe and nutritional quality by MAS. (c) 2018 Friends Science Publishers.
通讯机构：
[Xiao, Y.-H.] A;Agronomy College of Hunan Agricultural University / Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance / Southern Regional Collaborative Innovation Center for Grain and Oil Crops in ChinaChina
通讯机构：
[Wang, Guo-Liang] C;[Wang, Guo-Liang] O;Chinese Acad Agr Sci, Inst Plant Protect, State Key Lab Biol Plant Dis & Insect Pests, Beijing 100193, Peoples R China.;Ohio State Univ, Dept Plant Pathol, Columbus, OH 43210 USA.
关键词：
genome-wide association study (GWAS);host resistance;QTL;rice blast;SNP
摘要：
Resistance in rice cultivars to the rice blast fungus Magnaporthe oryzae is complex and is controlled by both major genes and quantitative trait loci (QTLs). We undertook a genome-wide association study (GWAS) using the rice diversity panel 1 (RDP1) that was genotyped using a high-density (700 000 single nucleotide polymorphisms) array and inoculated with five diverse M. oryzae isolates. We identified 97 loci associated with blast resistance (LABRs). Among them, 82 were new regions and 15 co-localized with known blast resistance loci. The top 72 LABRs explained up to 98% of the phenotypic variation. The candidate genes in the LABRs encode nucleotide-binding site leucine-rich repeat (NBS-LRR) resistance proteins, receptor-like protein kinases, transcription factors and defence-related proteins. Among them, LABR_64 was strongly associated with resistance to all five isolates. We analysed the function of candidate genes underlying LABR_64 using RNA interference (RNAi) technology and identified two new resistance alleles at the Pi5 locus. We demonstrate an efficient strategy for rapid allele discovery using the power of GWAS, coupled with RNAi technology, for the dissection of complex blast resistance in rice.
