陆地棉HB红花性状特异SCAR分子标记的开发

利用Operon系列引物筛选到1个与HB红花性状基因连锁的RAPD标记OPA15^1160，对差异条带进行克隆与核苷酸测序，根据测序结果设计SCAR引物，在HB红花近等基因系及其白花轮回亲本中进行PCR扩增程序优化和鉴定，筛选出一对引物可稳定扩增出与HB红花性状基因连锁的特异片段，获得了与HB红花性状基因紧密连锁的SCAR标记HB^-330。利用具黄色花瓣紫红色基斑的海岛棉与粉红花瓣的红叶棉等种质材料以7LHB红花近等基因系与白花轮回亲本杂交的F1、BC1F1、F2群体，对该SCAR标记的特异性与准确性进行了鉴定与验证，在红花植株中扩增出了330bp大小的片段而在白花植株中未扩增出，证明该标记准确性高、重复性好。HB红花是通过远缘杂交转自野生二倍体比克氏棉的性状，已成功地应用于性状标记杂交棉育种。该SCAR标记不仅为HB红花标记杂交种的纯度鉴定提供了有效技术手段，也为新品种保护提供了技术支持，促进了红花性状杂交种的分子标记辅助育种进程。

Development of a SCAR Marker Linked to HB Red-Corolla Gene in Cotton

In this study, a RAPD marker （OPA15^-1160） was screened from the Operon RAPD primers, which showed linkage relation with HB red-corolla gene. The specific amplified fragment was extracted and purified for sequencing. According to the sequence, specific primers of sequence characterized amplified region （SCAR） were designed and screened. The SCAR primers were amplified in island cotton （with yellow petals and purple base spot）, red leaf cotton （with pink petals）, HB red-corolla near-isogenic lines and recurrent parent with white corolla as well as their hybrid F1, BC1F1, F2 populations. There was a specific fragment about 330 bp in red-corolla plants and no PCR amplification in white corolla plants, which proved that the HB^-330 was a specific SCAR marker of HB red-corolla traits with high accuracy and repeatability. The HB red-corolla trait was transferred from the wild diploid Gossypium bickii via distant hybridization, and this trait has been successfully applied to hybrid cotton breeding. Development of this SCAR marker provides an effective technical method of protecting HB red-corolla cotton varieties and germplasm sources and identifying quality of hybrid cotton seeds. This SCAR marker accelerates the process of marker-assisted selection for breeding of hybrid cotton with HB red-corolla trait.