利用四交群体构建陆地棉栽培品种间的SSR标记遗传图谱

Genetic linkage mapping based on SSR marker with a four-way cross population in Gossypium hirsutum L.

作物遗传作图与QTL定位常应用在源于两自交系的单交群体上,是利用2个亲本之间的遗传多态信息;而育种实践中经常用到的四交群体却很少用于遗传作图。本研究将异交物种中F1分离群体的作图方法应用于常异花授粉作物棉花上,以4个陆地棉栽培品种泗棉3号、苏棉12、中4133和8891为亲本,构建陆地棉品种间四交作图群体泗棉3号/苏棉12//中4133/8891,利用JoinMap3.0构建了1张陆地棉栽培品种间的SSR标记遗传图谱。该图谱由56个连锁群组成,总长为2113.3cM,含有286个SSR多态位点,覆盖率达42.3%;单个连锁群的标记数2-24个,平均5.2个;长度为0.37-125cM,平均38.4cM;标记间的平均距离为7.4cM。这是目前报道的第1张覆盖率达40%的陆地棉栽培品种间的分子标记遗传图谱。

Linkage and QTL mapping in crops have been applied mainly to single cross population derived from two inbred lines,and only polymorphism information between two parents was employed to develop linkage map.Four-way cross population was rarely used to construct linkage map in crops.In this paper,the method of linkage mapping used in heterozygous F1 was applied to cotton,an often-crossed pollination crop,and four upland cotton cultivars（Gossypium hirsutum L.）,Simian 3,Sumian 12,Zhong 4133 and 8891 were used to develop a four-way cross population,Simian 3/Sumian 12//Zhong 4133/8891.A linkage map was constructed based on SSR markers with JoinMap3.0.The linkage map was comprised of 56 linkage groups spanning a distance of 0.37 cM to 125 cM with 286 mapped loci.These loci covered 2 113.3 cM,which was estimated as 42.3% of the total recombination length of the cotton genome.The average genetic distance between two loci was 7.4 cM.This is the first linkage map with distance beyond 40% of the total recombination length of the cotton genome.