title: QTL analysis on rice grain appearance quality, as exemplifying the typical events of transgenic or backcrossing breeding.
abstract: Rice grain shape and yield are usually controlled by multiple quantitative trait loci (QTL). This study used a set of F9-10 recombinant inbred lines (RILs) derived from a cross of Huahui 3 (Bt/Xa21) and Zhongguoxiangdao, and detected 27 QTLs on ten rice chromosomes. Among them, twelve QTLs responsive for grain shape/ or yield were mostly reproducibly detected and had not yet been reported before. Interestingly, the two known genes involved in the materials, with one insect-resistant Bt gene, and the other disease-resistant Xa21 gene, were found to closely link the QTLs responsive for grain shape and weight. The Bt fragment insertion was firstly mapped on the chromosome 10 in Huahui 3 and may disrupt grain-related QTLs resulting in weaker yield performance in transgenic plants. The introgression of Xa21 gene by backcrossing from donor material into receptor Minghui 63 may also contain a donor linkage drag which included minor-effect QTL alleles positively affecting grain shape and yield. The QTL analysis on rice grain appearance quality exemplified the typical events of transgenic or backcrossing breeding. The QTL findings in this study will in the future facilitate the gene isolation and breeding application for improvement of rice grain shape and yield.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Bao
authors.initials: B
authors.lastname: Yan
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Rongjia
authors.initials: R
authors.lastname: Liu
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Yibo
authors.initials: Y
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Guanjun
authors.initials: G
authors.lastname: Gao
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Qinglu
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Xing
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Life Science, Heilongjiang University , Haerbin 150080 , China.
authors.forename: Gonghao
authors.initials: G
authors.lastname: Jiang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan) and National Center of Crop Molecular Breeding, Huazhong Agricultural University , Wuhan 430070 , China.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: He
keywords: Bt gene; Oryza sativa L.; QTL; grain shape and weight