芝麻产量相关性状与SSR标记的关联分析

摘要

Sesame is an important traditional oil crop.In order to explore the gene loci controlling of yield-related traits,we screened a total of 72 SSR markers to evaluate the diversity and population structure among 96 varieties of sesame seeds from home and abroad.Through analyzing population structure,association analysis between SSR markers and 8 yield traits including plant height (PH),height of stem from base to first capsule (SH),seed numbers per capsule (SC),capsule width (CW),capsule length (CL),stem tip (ST),capsule numbers per plant (CP) and 1000-grain weight (PH) were performed using TASSEL MLM (mixed linear model) programs.The result showed followings:(1)A total of 446 alleles were found,and the average alleles per locus were 6.2,which varied from 2 to 14.The polymorphism information content (PIC) value ranged from 0.242 1 to 0.821 0,with an average of 0.540 7.The gene diversity index ranged from 0.550 4 to 0.989 7,with a mean of 0.747 7.(2) The analysis of population genetic structure divided the experimental materials into three subgroups.(3) Association analysis found that there were 51 markers associated with 5 yield traits,with the rate of phenotypic variation explained from 0.132 9 to 0.320 8.Among them,5 loci were associated with the same trait in multiple environments or using the average values,which were more stable alleles,for example,SSR loci Hs1775-A2 and SIM201-A1 which were associated with the height of the plant(PH).The marker sites Hs1514-A1,SIM004-A3 and SIM002 -A1 associated with the seed number per capsule(SC),the height of stem from base to first capsule (SH) and capsule numbers per plant (CP) respectively.%为挖掘控制芝麻产量相关性状的基因位点,本研究利用多态性较高的72个SSR标记,对来自国内外96份芝麻品种资源进行遗传多样性和群体遗传结构分析,在此基础上采用TASSEL3.0软件的MLM(Mixed Linear Model)方法对株高、株蒴数、每蒴粒数、蒴长、蒴宽、千粒重、始蒴部位、空稍尖8个产量相关性状进行SSR标记的关联分析.结果表明:72个标记共检测出446个等位变异,变异范围为2～14个,平均6.2个;引物的多态性信息含量(PIC)变异范围为0.242 1～0.821 0,平均为0.5407;基因多样性指数的变异范围在0.5504 ～0.989 7,平均值为0.747 7.群体遗传结构分析将供试材料分为3个亚群.关联分析结果显示,51个标记位点与株高、蒴长、每蒴粒数、始蒴部位、空稍尖显著关联,各标记对表型变异的解释率在13.29％ ～ 32.08％.有5个位点在多个环境或均值下被重复检测到,是较为稳定等位变异,如与株高相关联的位点Hs1775-A 2、SIM201-A1;与每蒴粒数、始蒴部位和株蒴数分别关联的标记位点Hs1514-A1、SIM004-A3和SIM002-A1.