Working group session:
Comparative Genomics and Bioinformatics
Presentation type:
poster
Authors:
Zhu, Jun; Du, Xiongming
Presenter:
Zhu, Jun
Correspondent:
Zhu, Jun; Du, Xiongming
Abstract:
Cotton yield and fiber quality are complex traits controlled by polygenes involving epistasis and environment interaction. Association mapping was performed to detect associated between agronomy traits with 142 SSRs in A sub-genome and 178 SSRs in D sub-genome of 323 accessions of Gossypium hirsutum L. in 9 environments. A mixed linear model including epistasis and environmental interaction was used to screen associate loci. There were total 252 SSRs detected for yield and its three components (99 for lint yield, 171 for boll number, 164 for boll weight, and 150 for lint percentage). These significant loci explain about 62.05% of the phenotypic variance (h2(G+GE)=49.06~ 72.29%). It was indicated by high contribution of environmental interaction to the phenotypic variance for lint yield and boll numbers, that genetic effects of SSR loci were susceptible to environment factors. For three fiber traits, total 320 SSRs were identified (203 for fiber length, 159 for fiber strength, and 73 for micronaire value). Additive and epistasis effects were both significant to three traits, but epistasis effects were the leading genetic effects to fiber length (h2(AA) =49.64) and additive effects were the primary genetic component of fiber strength (h2(A)=30.39) and fiber micronaire value (h2(A)=12.38). The heritability of environment interaction effects was relatively small, indicating that three fiber traits could be expressed stably in various environments. The additive loci tended to be located in the A sub-genome, and the digenic epistasis loci were more like to arise interactions within D sub-genome as well as between A sub-genome and D sub-genome. These results provided insights into the genetic basis of cotton complex traits and may be useful for marker-assisted breeding to improve cotton production.