基于AFLP分子标记分析陕西省保存主要家蚕品种的遗传多样性及亲缘关系

An Analysis on Genetic Diversity and Phylogenetic Relationship Among Main Silkworm(Bombyx mori) Varieties Preserved in Shaanxi Province Based on AFLP Molecular Markers

采用AFLP分子标记技术分析陕西省保存的53个代表性家蚕品种的遗传多样性,为合理利用品种资源,选育适合西北蚕区饲养的优良家蚕品种提供理论依据。用供试品种滞育期的蚕卵提取基因组DNA,选用重复性较好的14对引物组合进行AFLP扩增,共获得535个条带,其中有472个条带呈多态性,多态性比率为88.22%。采用UPGMA方法对供试品种间的亲缘关系进行聚类分析,53个品种间的遗传距离为0.072 8～0.601 9,主要分为中系、日系和欧系3大类群,其中:日系和欧系品种遗传距离较近,与传统的家蚕系统按来源地分类的结果吻合;4个陕西地方一化三眠蚕品种明显有别于其它家蚕品种而归为一个特殊类群,提示其具有独特的种质特性。此外,采用滞育期的蚕卵提取家蚕基因组DNA,可以克服取样的时间限制,满足实验需要。

The genetic diversity of 53 silkworm （ Bombyx mort） varieties preserved in Shaanxi Province was analyzed by AFLP molecular marker technology to provide theoretical basis for rationally utilizing silkworm germplasm resources and breeding of excellent silkworm varieties suitable for rearing in sericultural areas of northwest China. By using the genomic DNA extracted from diapause eggs of the tested silkworm varieties and 14 primer combinations with good re- peatability, totally 535 bands were amplified by AFLP, among which 472 bands showed polymorphism. The polymor- phic percentage was 88.22%. Phylogenetic relationship between these tested varieties was analyzed with UPGMA method. The result showed that the genetic distance between 53 silkworm varieties was within the range of 0. 072 8 to 0. 601 9. These silkworm varieties were divided into three groups namely Chinese, Japanese and European strains. A-mong them, the Japanese and European strains had close genetic distance, being consistent with the traditional classification results based on origination site of silkworm systems. Four monovoltine trimoiter silkworm varieties from Shaanxi region obviously differed with other silkworm varieties and formed a special group, sugges- ting that they had unique germplasm characteristics. In addition, genomic DNA extraction from silkworm dia-pause eggs could overcome the limitation of sampling time and satisfy the needs of experimental analysis.