以171个F2双核体菌株为作图群体,通过相互配对的2个单核体的基因型推断双核体基因型,构建了第一张基于双核体群体的香菇遗传图谱。该图谱包含分布于15个连锁群的459个标记,覆盖长度为989.7cM,平均标记间隔为2.2cM。此外,以此双核体群体作为表型分离群体,定位了6个与香菇双核体菌丝生长速度相关的QTLs,位于5个连锁群上。采用全同胞单核体随机交配策略,易于构建相对大的双核体群体,用于连锁图构建和QTL定位。研究表明,在食用菌连锁图谱构建及QTL定位研究中,利用F2群体,可能为提高遗传作图效率,解决作图群体与表型分离群体间不一致问题提供新的途径。
171 F2 dikaryons derived from randomly mating individuals of the full-sib monokaryons of Lentinula edodes were served as mapping population. An easy method using genotype data deduced from the two mating monokaryons was applied to construct a new linkage map of L. edodes. The first dikaryon map for L. edodes constructed here included 459 markers assigned to 15 linkage groups, and covered a total genetic length of 989.7cM with an average marker spacing of 2.2cM. In addition, the dikaryon population was employed as phenotypic segregation population to map quantitative trait loci (QTLs) controlling mycelium growth rate of L. edodes dikaryon. Consequently six putative QTLs controlling mycelium growth rate were identified in five linkage groups. Results indicated that using F2 dikaryons from randomly mating individuals of full-sib monokaryons was an easy way to construct a relatively large size of population both for linkage mapping and QTL mapping. The present work suggested that the utilization of F2 population provided a new possible way to improve the efficiency of genetic mapping, and to solve the inconsistency between the linkage mapping population and the phenotypic segregating population in edible mushrooms.