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以耐湿大麦品种泰兴9425与湿害敏感品种Franklin构建的DH系及亲本为材料,在湿害胁迫条件下,考察了大麦苗期与耐湿性相关的根长、根鲜质量、根干质量、茎叶鲜质量和茎叶干质量,各性状均表现为连续分布,且都存在一定数量的双向超亲遗传类型,为多基因控制的数量性状。结合已构建的分子连锁图谱,采用Windows QTL Cartographer 2.5软件中的复合区间作图法进行QTL定位分析。5个根系及茎叶性状共检测到13个QTL,除第2、5染色体外,其他染色体上均有分布,LOD值为2.59~3.83,对表型变异的解释率为10.99%~20.7%。其中最大根长检测到2个QTL,控制根系鲜质量和干质量的QTL分别为2,3个,与茎叶鲜质量和干质量相关的均为3个。在第6、7染色体存在QTL成簇分布的现象,表明可能存在一因多效或QTL紧密连锁的情况。为大麦苗期耐湿相关根系性状的分子标记辅助选择育种奠定了基础。
The root length, root fresh weight, root dry weight and root dry weight of barley were studied under wet stress conditions with Taibing 9425 and DH strain and their parents, which were susceptible to drought-resistant barley varieties Franklin. Leaf fresh weight and dry weight of stems and leaves, all traits showed continuous distribution, and there are a certain number of bi-directional super-progeny genetic type, the quantitative trait controlled by multiple genes. Combined with the constructed molecular linkage map, QTL mapping analysis was performed using the composite interval mapping method in Windows QTL Cartographer 2.5 software. Thirteen QTLs were detected in five root and stem and leaf traits, with the exception of chromosomes 2 and 5 on other chromosomes. The LOD values ranged from 2.59 to 3.83, and the explanations for phenotypic variation ranged from 10.99% to 20.7%. Among them, two QTLs were detected at the maximum root length, and two or three QTLs controlling root fresh weight and dry weight respectively were found, which were all related to fresh and dry weight of stems and leaves. The presence of QTL clustering on chromosomes 6 and 7 suggests that there may be a case of pleiotropic or QTL close linkage. Which laid the foundation for molecular marker-assisted selection breeding of related root traits of barley at the seedling stage.