玉米秸秆消化率全基因组关联分析

Genome-Wide Association Study of Digestibility of Straw in Maize

48h体外干物质消化率(48h in vitro dry matter digestibility,48h IVDMD)是衡量青贮玉米品质的重要指标。为了初步探究玉米秸秆消化率的分子遗传机理,以341份玉米自交系为材料,于2018年在沈阳和通辽种植,收获后测定秸秆48h IVDMD。利用全基因组重测序获得的6276612个高质量SNPs进行全基因组关联分析,共检测到153个与玉米秸秆消化率显著相关的SNPs位点(P<1.0×10^-6),4个SNPs显著水平在P<1.0×10^-8以上;共找到38个秸秆消化率的候选基因,主要涉及细胞生长发育、防御反应和信号转导等生物学功能。

The 48 h dry matter digestibility(48 h IVDMD) is an important index to measure the quality of silage maize. In order to explore the molecular genetic mechanism of digestibility of 48 h IVDMD, 341 maize inbred lines were evaluated for 48 h IVDMD in 2018 in Shenyang and Tongliao. These inbred lines were subjected to whole genome sequencing, generating a total of 6 276 612 high quality SNPs. GWAS analysis detected 153 SNPs using the threshold of P <1.0×10^-6 and 4 SNPs using the threshold of P < 1.0×10^-8. Thirty-eight candidate genes were identified based on the GWAS, and the biological functions of these genes were mainly involved in cell growth and development, defense reaction, and signal transduction.