中国西南地区芥菜型油菜资源遗传多样性分析

Genetic Diversity Analysis of Brassica juncea Landraces in Southwest China

【目的】研究中国西南地区丰富的芥菜型油菜资源遗传多样性,为芥菜型油菜资源的保护和育种利用提供有益的数据。【方法】选取以西南地区为主的73份芥菜型油菜资源,分别进行14个随机引物RAPD标记多态性分析结果的聚类分析和15个主要植物学性状量测数据的聚类分析。【结果】RAPD标记多态性分析结果的聚类分析显示为3大类,共15个亚类:四川盆地资源为第1大类,含川东、川南、川北和重庆来源等6个亚类;盆周及盆周高原和云南部分资源为第2大类,分川东南、川西南和川西北来源等4个亚类;云贵高原及长江两岸为第3大类,以贵州、云南来源的资源为主,分贵阳周边、金沙江流域和云南中部来源等5个亚类。植物学性状量测数据的聚类分析显示为4大类,共14个亚类:第1大类以川东南、重庆和云南来源的资源为主,分3个亚类;第2大类以川南、川北、云南和贵州来源的资源为主,分4个亚类;第3大类以贵州、四川来源的资源为主,分4个亚类;第4大类以川西北来源的资源为主,含3个亚类。【结论】西南地区芥菜型油菜资源间差异明显,具有丰富的遗传多样性;RAPD标记多态性分析结果和植物学性状量测数据的聚类分析结果,显示分类主要遵循地域和生态环境规律,可分清芥菜型油菜资源间的亲缘关系和遗传距离远近;在分子水平上,分类结果可能更深入和准确可靠。

[Objective] Evaluation of the genetic diversity of the rich rapeseed landraces （Brassica juncea L.） in Southwest China can provide useful information for germplasm conservation and utilization in rapeseed breeding. [Method] Seventy-three landraces were analyzed by cluster analysis of genetic relationship by data of RAPD polymorphic marker and of 15 agronomic traits investigated. [Result] The cluster analysis of RAPD marker showed that the landraces were classified into three groups and 15 subgroups. The landraces in the first group from the Sichuan Basin could be divided into six subgroups, including East Sichuan, South Sichuan, North Sichuan and Chongqing, etc. The landraces in the second group from regions around the Sichuan Basin was divided into Southeast Sichuan, South Sichuan, Southwest Sichuan and Northwest Sichuan subgroups. The landraces from the Yunnan-Guizhou Plateau and the Yangtze River valley fell into the third group, which was divided into five subgroups, such as Guiyang district, Jinshajiang River valley and Middle Yunnan et al. The cluster analysis of agronomic traits showed that the landraceswere classified into four groups and 14 subgroups. Group Ⅰ, in which landraces were mainly from Southeast Sichuan, Chongqing and Yunnan, was divided into three subgroups. Group Ⅱ, in which landraces were mainly from Sichuan, Yunnan and Guizhou, was divided into four subgroups. Group Ⅲ, in which landraces were mainly from Guizhou and Sichuan, was divided into four subgroups. Group IV, in which landraces were mainly from Northwest Sichuan plateau, was divided into three subgroups. [Conclusion] The differences among the landraces of B. juncea in Southwest China were significant with a high level of genetic diversity. The genetic relationship of landraces was decided by the specific ecological environment and the local cultivation customs as well, while was not always in accordance with ecological regions. Although both RAPD marker and agronomic traits could be used for the cluster analysis of genetic distance of the landraces in B. juncea, molecular marker, RAPD, would be more reliable than agronomic traits.