EST辅助的甘蓝型油菜显性核不育AFLP标记转化

甘蓝型油菜显性核不育广泛应用于轮回选择和杂种优势利用，不育基因标记的开发与应用对于基因克隆和育种实践具有重要意义。基于AFLP标记SA12MG14的序列信息，从拟南芥整合数据库中，检索与标记序列同源的甘蓝型油菜EST，结合标记和EST序列设计特异引物，转化成新的SCAR标记。获得的SCAR标记S6B3，具有很高的检测稳定性，在回交群体Popu2上分析验证，结果与AFLP标记完全一致。该标记与不育基因相距0.3 cM，将其用于临保系同源的纯合型不育系选育，可有效提高育种工作效率。

EST-Aided Conversion of AFLP Marker Linked to Dominant Male Sterility Gene in Brassica napus into SCAR

Dominant genic male sterility (Ms) in Brassica napus has been widely utilized in recurrent selection and in heterosis application. Recent genetical studies verified that its restorer gene is an allele locating at the Ms gene locus. According to this genetic pattern, a whole sterile population (Msms) can be acquired by crossing a homozygous male sterile line (MsMs) with a temporary maintainer (msms) and further used as a female parent in hybrid production, but trans-breeding of the sterile line or the temporary maintainer line that has the same nuclear background with the temporary maintainer line or the sterile line is critical to obtain uniform hybrid population and to maintain heterosis. Because of being laborious and time-consuming, an AFLP marker is usually converted to a PCR marker which is more efficient in molecular marker-assisted selection. In present study, we developed a SCAR marker with bioinformatics method from an AFLP marker SA12MG14 tightly linked to the Ms. Homologous sequences for this marker were obtained through Blast search (http://www.ncbi.nlm.nih.gov), and a corresponding accession of EST from Brassica napus was found from the Arabidopsis thaliana Integrated Database (http://atidb.org/cgi-perl/gbrowse/atibrowse). According to the combined sequence information of the AFLP fragment and the EST, a pair of primers was designed and analyzed on a backcross population Popu2. A dominant SCAR marker S6B3 was successfully identified and further detected consistently on the population with the original AFLP marker. The detected band was clear and steady. This marker is 0.3 cM away from the Ms, and its practical application will enhance work efficiency of breeding for homozygous sterile lines homologous to corresponding temporary maintainers.