甘蓝型油菜高／低含油量近等基因系构建及鉴定

摘要

To explore the mechanism of regulation of fatty acid metabolism,find valuable high oil genes and provide based material for high quality breeding in Brassica napus L.,the near-isogenic lines of high /low oil content was constructed.After continuous self crossing two generations,30 sister lines with same agronomic traits and differ-ent oil content were chosen based on high oil line,NJ9.Final nine near-isogenic line were obtained.1 56 pairs of SSR primers derived from Brassica DB public databases were used for PCR amplification of nine protocol near-iso-genic line meterials,and 32 pairs of primers were screened for near-isogenic analysis.The results of genetic similari-ty coefficient estimation and clustering analysis,based on PCR amplification result,showed that the genetic similarity coefficients of 9 candidate strains were between 0.85 and 0.94,and the genetic similarity coefficient of YC1 3-554 and YC1 3-559 was 0.94,which was identified as near isogenic line.Based on the results of the investigation and a-nalysis of agronomic traits in the mature period,the YC1 3-559 and YC1 3-554 were identified as high oil content and low oil near isogenic line.This study proves that using the method of continuos self cross and directional selection could be used to build nearly-isogenic lines and enriched the resource of nearly-isogenic lines.%为了探讨油菜种子中脂肪酸代谢调控的机制，发现有价值的高油基因，为高油育种研究提供基础材料，构建了甘蓝型油菜高／低含油量近等基因系。以高油品系 NJ9为基础试材，连续自交2代后，选择农艺性状基本一致、含油量不同的姐妹系30份，进行连续自交和含油量的选择，最终获得9份拟近等基因系材料。以来源于芸薹属 DB 公共数据库的156对 SSR 引物对9份拟近等基因系株系材料进行扩增，筛选出32对引物用于近等性分析。基于32对SSR 引物 PCR 扩增结果，经过遗传相似性系数估算以及聚类分析，结果显示，9份拟近等基因系试材遗传相似性系数均为0．85～0．94，其中，YC13-554和 YC13-559的遗传相似性系数最大，为0．94，确定其为近等基因系。成熟期农艺性状调查结果，进一步确定 YC13-554和 YC13-559为高／低含油量近等基因系。结果表明，连续自交和定向选择的方法可用于构建近等基因系，丰富了近等基因系的来源。