title: Association Mapping for Fiber-Related Traits and Digestibility in Alfalfa (Medicago sativa).
abstract: Association mapping is a powerful approach for exploring the molecular genetic basis of complex quantitative traits. An alfalfa (Medicago sativa) association panel comprised of 336 genotypes from 75 alfalfa accessions represented by four to eight genotypes for each accession. Each genotype was genotyped using 85 simple sequence repeat (SSR) markers and phenotyped for five fiber-related traits in four different environments. A model-based structure analysis was used to group all genotypes into two groups. Most of the genotypes have a low relative kinship (<0.3), suggesting population stratification not be an issue for association analysis. Generally, the Q + K model exhibited the best performance to eliminate the false associated positives. In total, 124 marker-trait associations were predicted (p < 0.005). Among these, eight associations were predicted in two environments repeatedly and 20 markers were predicted to be associated with multiple traits. These trait-associated markers will greatly help marker-assisted breeding programs to improve fiber-related quality traits in alfalfa.
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agriculture Sciences Beijing, China.
authors.forename: Zan
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agriculture Sciences Beijing, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Qiang
authors.affiliation: Institute of Dry Farming, Hebei Academy of Agriculture and Forestry Sciences Hengshui, China.
authors.forename: Haiming
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Grassland Science, China Agricultural University Beijing, China.
authors.forename: Ruixuan
authors.initials: R
authors.lastname: Xu
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agriculture Sciences Beijing, China.
authors.forename: Zhengli
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agriculture Sciences Beijing, China.
authors.forename: Hongwen
authors.initials: H
authors.lastname: Gao
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agriculture Sciences Beijing, China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Institute of Dry Farming, Hebei Academy of Agriculture and Forestry Sciences Hengshui, China.
authors.forename: Guibo
authors.initials: G
authors.lastname: Liu
authors.affiliation: Department of Grassland Science, China Agricultural University Beijing, China.
authors.forename: Yingjun
authors.initials: Y
authors.lastname: Zhang
keywords: Simple sequence repeat (SSR); alfalfa; association mapping; fiber-related traits