玉米吐丝期叶绿素指数全基因组关联分析

Genome Wide Association Analysis for Chlorophyll Index at Silking Stages in Maize

叶绿素是植物形成产量的重要因子。为了探究吐丝期叶绿素的遗传机理和代谢机制,本研究以榆林、杨凌两地126份玉米自交系为材料,采用全基因组关联分析的方法将简化基因组测序填充过滤筛选后得到31561个SNP(Single nucleotide polymorphism)标记,结合叶绿素指数SPAD(Soil and plant analyzer develotrnent)值以及BLUP(Best linear unbiased prediction)值进行分析,共检测到37个显著性关联SNP标记;在LD(Linkage disequilibrium)衰退有效距离上下150 kb内检测到201个候选基因,进一步进行GO富集注释和分析,将叶绿素相关候选基因主要锚定在过氧化氢代谢过程、受体活性、活性氧代谢过程和氮化合物代谢过程的负调控等18个代谢途径上。本研究进一步探究了叶绿素相关代谢遗传机理,对高光效育种和提高作物产量有重要意义。

The chlorophyll is an important factor for plant production.In order to dissect the genetic and metabolic mechanism of chlorophyll during silking stage in maize,126 inbred lines were planted in Yulin and Yangling for collecting the SPAD value and sequenced by simplified genome sequencing.GWAS(Genome-wide association study)was conducted for SPAD value collected from the two environments using 31561 high-quality SNP markers.Altogether,37 significant SNP sites were identified.Based on the LD decay distance of the population(150 kb),201 candidate genes were identified in confidence interval.After GO enrichment and annotation analysis,these candidate genes related to chlorophyll synthesis were mainly involved in 18 different metabolisms such as hydrogen peroxide metabolism,receptor activity,active oxygen metabolism and negative regulation of nitrogen compounds metabolism.This study further explored the genetic mechanism of chlorophyll related metabolism,which is of great significance to breed new hybrids with high light efficiency and improve crop yield.