陆地棉亚红株突变体基因的初步定位

陆地棉亚红株突变体PD-17与GK19杂交F₁代表现出良好的光合作用效率，具有较高的超亲优势，是潜在的优良种质资源。寻找与该突变基因Rs连锁的分子标记并进行染色体定位，对于该基因的进一步精细定位或克隆具有重要的意义。以亚红株突变体PD-17与GK19配置的BC1群体为作图群体，选用覆盖棉花所有已鉴定染色体及大多数连锁群的419对SSR引物，利用BSA（bulked segregation analysis）法筛选有多态性差异引物，然后根据群体单株基因型进行作图分析。结果显示，位于第7条染色体上的5个分子标记与Rs基因相连锁，SSR标记BNL2634与Rs基因的遗传距离较小，约为10.3 cM，SSR标记CIR393位于Rs基因另一侧，与Rs基因的遗传距离约为29.1 cM，由此，可将Rs基因定位于第7染色体上。

Gene Mapping of a Sub-Red Mutant in Upland Cotton

Sub-red mutant,used as a female parent,was crossed with GK19 to generate F1 plants,which surpassed their parents with its good photosynthesis efficiency.In this sense,sub-red mutant would be regarded as a potentially elite germplasm.Molecular markers linked to sub-red mutant gene are of great importance for fine mapping the sub-red gene and cloning.To screen for SSR markers closely linked to sub-red gene in upland cotton,we developed the F1 and BC1 from intraspecific crosses with the parents mentioned above.Screening of 419 SSR markers,covering all the identified chromosomes and most linkage groups of cotton,was performed by bulked segregation analysis,revealing informative SSRs,mapped on the above populations afterwards.One co-dominant SSR marker BNL2634 was identified closely linked to the sub-red gene(tentatively named as Rs),with an estimated distance of 10.3 cM,depending on the population used.The other five markers linked to Rs were CIR393,with a loose linkage to Rs(approximately 29.1 cM),CIR335,BNL1597,NAU1362,and NAU1048,showing the Rs gene to be located on cotton chromosome 7.