Mapping and genetic validation of a grain size QTL qGS7.1 in rice (Oryza sativa L.)

• Published in: Journal of Integrative Agriculture Vol. 18; no. 8; pp. 1838 - 1850
• Main Authors: XUE, Pao, ZHANG, Ying-xin, LOU, Xiang-yang, ZHU, Ai-ke, CHEN, Yu-yu, SUN, Bin, YU, Ping, CHENG, Shi-hua, CAO, Li-yong, ZHAN, Xiao-deng
• Format: Journal Article
• Language: English
• Published: Zhejiang Key Laboratory of Super Rice Research/State Key Laboratory of Rice Biology/China National Rice Research Institute,Hangzhou 310006, P.R.China%Zhejiang Key Laboratory of Super Rice Research/State Key Laboratory of Rice Biology/China National Rice Research Institute,Hangzhou 310006, P.R.China 01.08.2019; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P.R.China%Zhejiang Key Laboratory of Super Rice Research/State Key Laboratory of Rice Biology/China National Rice Research Institute,Hangzhou 310006, P.R.China; Institute of Crop Breeding and Cultivation, Shanghai Academy of Agricultural Sciences, Shanghai 201403, P.R.China; Nanchong Academy of Agricultural Sciences, Nanchong 637000, P.R.China%Zhejiang Key Laboratory of Super Rice Research/State Key Laboratory of Rice Biology/China National Rice Research Institute,Hangzhou 310006, P.R.China; KeAi Communications Co., Ltd
• Subjects: backcrossing; China; chromosomes; grain size; grain weight; grain yield; heterozygosity; inbred lines; Oryza sativa; phenotypic variation; quantitative trait loci; residual heterozygote; rice; rice (Oryza sativa L.); China; rice (Oryza sativa L.); grain size; quantitative trait loci; grain weight; residual heterozygote
• ISSN: 2095-3119
• DOI: 10.1016/S2095-3119(18)62113-6

Grain size is a major determinant of grain weight, which is one of the components of rice yield. The objective o this study was to identify novel, and important quantitative trait loci (QTLs) for grain size and weight in rice. QTLs were mapped using a BC4F4 population including 192 backcross inbred lines (BILs) derived from a backcross between Xiaolijing (XLJ) and recombinant inbred lines (RILs). The mapping population was planted in both Lingshui (Hainan, 2015) and Fuyang (Zhejiang, 2016), with the short- and long-day conditions, respectively. A total of 10 QTLs for grain length, four for grain width, four for the ratio of grain length to width, and 11 for grain weight were detected in at least one environment and were distributed across 11 chromosomes. The phenotypic variance explained ranged from 6.76–25.68%, 14.30–34.03%, 5.28–26.50%, and 3.01–22.87% for grain length, grain width, the ratio of grain length to width, and thousand grain weight, respectively. Using the sequential residual heterozygotes (SeqRHs) method, qGS7.1, a QTL for grain size and weight, was mapped in a 3.2-Mb interval on chromosome 7. No QTLs about grain size and weight were reported in previous studies in this region, providing a good candidate for functional analysis and breeding utilization.