甜瓜果实颜色3个质量性状基因的定位

Construction of a Highly Dense Genetic Map Using SNP and Mapping of Three Qualitative Traits in Cucumis melo

以甜瓜(Cucumis melo L.)黄绿皮、白肉、无覆纹的自交系‘K1-7’为母本,黄皮、橘红肉、无覆纹的自交系‘K3-92-1’为父本杂交,组建F2遗传群体,采用MSG(multiplexed shotgun genotyping)法对F2群体进行基因分型,并在甜瓜全基因组范围内扫描SNP遗传标记。利用检测到的44 722个SNP标记位点进行高密度Bin遗传图谱的构建,并对甜瓜果皮底色、覆纹颜色和果肉颜色等3个质量性状进行遗传分析和基因定位。结果表明,果皮底色和果肉颜色由单基因控制,黄绿果皮和橘红色果肉为显性性状,果皮底色基因定位在4号染色体409 828～835 625 bp区间内,长度约为425 kb,果肉颜色基因定位在9号染色体20 433 942～20 573 889 bp区间内,长度约为139 kb,覆纹颜色由两个有上位效应的基因控制,其中1个基因位点与果皮颜色控制位点在同一区域,1个基因定位在2号染色体末端23 736 803～23 787 235 bp区间内,长度约为51 kb。

A Bin map of melon was constructed using a F2 population developed from a crossing the melon inbred lines between‘K1-7'(green-yellow primary skin color,white flesh color and absence secondary skin color)and‘K3-92-1'(yellow primary skin color,red-orange flesh color and absence secondary skin color).A genotyping method based on restriction named MSG was applied to genotype for the F2 population,and then SNPs had been scaned in the genome-wide of melon.The Bin map included 44 722 SNPs,and then genetic analysis and gene maping had been done for primary skin color,secondary skin color and flesh color.Genetic analysis showed that the primary skin color and flesh color is determined by a single gene separately,in addition,the character of green-yellow primary skin color and red-orange flesh color is dominant inheritance.The genetic loci control of primary skin color was mapped on chromosome 4 of melon,narrowed the range of 409 828 bp to 835 625 bp(425 kb region),the genetic loci control of flesh color was mapped on chromosome 9,narrowed the range of 20 433 942 bp to 20 573 889 bp(139 kb region).The genetic control of secondary skin color was found to be complex,involving two loci with epistatic interactions.One of these loci was the same region as the genetic loci control of primary skin color trait,the other gene loci was mapping on chromosome 2,narrowed the range of 23 736 803 bp to 23 787 235 bp(51 kb region).