Abstract：
High yield has always been an essential target in almost all of the cotton breeding programs. Boll weight (BW) is a key component of cotton yield. Numerous linkage mapping and genome-wide association studies (GWAS) have been performed to understand the genetic mechanism of BW, but information on the markers/genes controlling BW remains limited. In this study, we conducted a GWAS for BW using 51,268 high-quality single-nucleotide polymorphisms (SNPs) and 189 Gossypium hirsutum accessions across five different environments. A total of 55 SNPs significantly associated with BW were detected, of which 29 and 26 were distributed in the A and D subgenomes, respectively. Five SNPs were simultaneously detected in two environments. For TM5655, TM8662, TM36371, and TM50258, the BW grouped by alleles of each SNP was significantly different. The ± 550 kb regions around these four key SNPs contained 262 genes. Of them, Gh_A02G1473, Gh_A10G1765, and Gh_A02G1442 were expressed highly at 0 to 1 days post-anthesis (dpa), - 3 to 0 dpa, and - 3 to 0 dpa in ovule of TM-1, respectively. They were presumed as the candidate genes for fiber cell differentiation, initiation, or elongation based on gene annotation of their homologs. Overall, these results supplemented valuable information for dissecting the genetic architecture of BW and might help to improve cotton yield through molecular marker-assisted selection breeding and molecular design breeding.
摘要：
高产一直是几乎所有棉花育种计划中的重要目标。棉铃重（BW）是棉花产量的关键组成部分。已经进行了许多连锁作图和全基因组关联研究（GWAS）以了解BW的遗传机制，但是有关控制BW的标记/基因的信息仍然有限。在这项研究中,我们在5种不同环境中使用51,268个高质量单核苷酸多态性(SNPs)和189个陆地棉进行了BW的GWAS.共检测到55个与BW显著相关的SNPs,其中29和26分布在A和D亚基因组中，分别。在两种环境中同时检测到五个SNP。对于TM5655、TM8662、TM36371和TM50258,按每个SNP的等位基因分组的BW是显著不同的。围绕这四个关键SNP的±550kb区域包含262个基因。其中,Gh_A02G1473、Gh_A10G1765和Gh_A02G1442在花后0至1天(dpa)高表达,-3到0dpa，TM-1胚珠中的-3至0dpa。它们被认为是成纤维细胞分化的候选基因，initiation,或基于其同源物的基因注释的延伸。总的来说,这些结果为解剖BW的遗传结构提供了有价值的信息，并可能有助于通过分子标记辅助选择育种和分子设计育种提高棉花产量。
