title: QTL Mapping of Kernel Number-Related Traits and Validation of One Major QTL for Ear Length in Maize.
abstract: The kernel number is a grain yield component and an important maize breeding goal. Ear length, kernel number per row and ear row number are highly correlated with the kernel number per ear, which eventually determines the ear weight and grain yield. In this study, two sets of F2:3 families developed from two bi-parental crosses sharing one inbred line were used to identify quantitative trait loci (QTL) for four kernel number-related traits: ear length, kernel number per row, ear row number and ear weight. A total of 39 QTLs for the four traits were identified in the two populations. The phenotypic variance explained by a single QTL ranged from 0.4% to 29.5%. Additionally, 14 overlapping QTLs formed 5 QTL clusters on chromosomes 1, 4, 5, 7, and 10. Intriguingly, six QTLs for ear length and kernel number per row overlapped in a region on chromosome 1. This region was designated qEL1.10 and was validated as being simultaneously responsible for ear length, kernel number per row and ear weight in a near isogenic line-derived population, suggesting that qEL1.10 was a pleiotropic QTL with large effects. Furthermore, the performance of hybrids generated by crossing 6 elite inbred lines with two near isogenic lines at qEL1.10 showed the breeding value of qEL1.10 for the improvement of the kernel number and grain yield of maize hybrids. This study provides a basis for further fine mapping, molecular marker-aided breeding and functional studies of kernel number-related traits in maize.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P. R. China.
authors.forename: Dongao
authors.initials: D
authors.lastname: Huo
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P. R. China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Ning
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P. R. China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Shen
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P. R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, P. R. China.|Hubei Collaborative Innovation Center for Grain Crops, Jingzhou 434025, P. R. China.
authors.forename: Zuxin
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D002874:Chromosome Mapping / Q000379:methods*; D003433:Crosses, Genetic; D005828:Genetics, Population; D006824:Hybridization, Genetic; D007178:Inbreeding; D010641:Phenotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D015203:Reproducibility of Results; D003313:Zea mays / Q000033:anatomy & histology* / Q000235:genetics*