title: Genome-wide Association Analyses Reveal the Genetic Basis of Stigma Exsertion in Rice.
abstract: Stigma exsertion, a key determinant of the rice mating system, greatly contributes to the application of heterosis in rice. Although a few quantitative trait loci associated with stigma exsertion have been fine mapped or cloned, the underlying genetic architecture remains unclear. We performed a genome-wide association study on stigma exsertion and related floral traits using 6.5 million SNPs characterized in 533 diverse accessions of Oryza sativa. We identified 23 genomic loci that are significantly associated with stigma exsertion and related traits, three of which are co-localized with three major grain size genes GS3, GW5, and GW2. Further analyses indicated that these three genes affected the stigma exsertion by controlling the size and shape of the spikelet and stigma. Combinations of GS3 and GW5 largely defined the levels of stigma exsertion and related traits. Selections of these two genes resulted in specific distributions of floral traits among subpopulations of O. sativa. The low stigma exsertion combination gw5GS3 existed in half of the cultivated rice varieties; therefore, introducing the GW5gs3 combination into male sterile lines is of high potential for improving the seed production of hybrid rice.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhou
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Pingbo
authors.initials: P
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Weibo
authors.initials: W
authors.lastname: Xie
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Saddam
authors.initials: S
authors.lastname: Hussain
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Yibo
authors.initials: Y
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Duo
authors.initials: D
authors.lastname: Xia
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Hu
authors.initials: H
authors.lastname: Zhao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Shengyuan
authors.initials: S
authors.lastname: Sun
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Junxiao
authors.initials: J
authors.lastname: Chen
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Ye
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Hou
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Da
authors.initials: D
authors.lastname: Zhao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Guanjun
authors.initials: G
authors.lastname: Gao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Qinglu
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Gongwei
authors.initials: G
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Xingming
authors.initials: X
authors.lastname: Lian
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Xiao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Sibin
authors.initials: S
authors.lastname: Yu
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Xianghua
authors.initials: X
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China. Electronic address: yqhe@mail.hzau.edu.cn.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: He
mesh_terms: D032461:Chromosomes, Plant / Q000235:genetics; D035264:Flowers / Q000235:genetics* / Q000378:metabolism; D055106:Genome-Wide Association Study / Q000379:methods*; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D040641:Quantitative Trait Loci / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000378:metabolism
keywords: GWAS; floral traits; grain shape; hybrid seed production; rice; stigma exsertion