基于GWAS的西瓜种子性状候选QTL鉴定

Identification of Candidate QTL for Watermelon Seed Traits Based on GWAS

【目的】为探究控制西瓜种子大小的遗传机制。【方法】以144份纯合西瓜种质为试材,对多环境下种子大小相关性状进行多样性指数分析、相关性分析和全基因组关联分析。【结果】144份种质资源种子长度、种子宽度与种子百粒重两两之间均呈极显著正相关;多样性指数分别为4.69、4.78和4.80;全基因组关联分析检测到3个过阈值的QTL区域,分别位于4、7和10号染色体上,其中位于7号染色体上的种子大小性状相关QTL区域在多次环境中均被检测到。【结论】西瓜种子大小是复杂的数量性状,其QTL在多个染色体上均有分布。

【Objective】To explore the genetic mechanism controlling the seed size of watermelon.【Method】Using 144 homozygous watermelon germplasms as test materials,the diversity index analysis,correlation analysis and genome-wide association analysis of seed size-related traits in multiple environments were carried out.【Result】There was a significant positive correlation between seed length,seed width and 100-seed weight of 144 germplasm resources;the diversity indexes were 4.69,4.78 and 4.80,respectively;the whole-genome association analysis detected 3 threshold values,the QTL regions of are located on chromosomes 4,7 and 10,respectively. The QTL regions related to seed size traits on chromosome 7 have been detected in multiple environments.【Conclusion】Watermelon seed size is a complex quantitative trait,and its QTL is distributed on multiple chromosomes.