三种紫球藻亲缘关系RAPD分析

利用RAPD技术对铜绿紫球藻（Porphyridium aerugineum 755），淡色紫球藻（Porphyridium purpureum 806）和紫球藻（Porphyridium cruentum）的亲缘关系进行分析。从50个随机引物中筛选出25个种间多态性较强，重复性较好的引物。检测到233个位点。在233个条带中有186个多态性位点。多态位点比率为79.73%，平均每个引物扩增9个条带，多态性条带7个。聚类分析结果表明：铜绿紫球藻、淡色紫球藻和紫球藻之间的平均遗传距离为0.455，其中铜绿紫球藻和淡色紫球藻之间的遗传距离为0.413，铜绿紫球藻和紫球藻之间的遗传距离为0.556，淡色紫球藻和紫球藻之间的遗传距离最小为0.396。所以由RAPD试验的分析结果可以得出:三种紫球藻为独立的种, 其中淡色紫球藻和紫球藻是亲缘关系较近的两个不同种。紫球藻属种间个体DNA多态性比较丰富，因此利用RAPD技术可以从DNA水平上检测紫球藻属种间差异。

Relationship Analysis of Three Species of Porphyridium by RAPD

The phylogenetic relationships of three species of Porphyridium, Porphyridium aerugineum 755, Porphyridium purpureum 806 and Porphyridium cruentum were analyzed by RAPD. Twenty-five random primers of high reproducible and stable quality were screened from 50 primers. There were 186 polymorphic fragments of 233 total fragments. The cluster analysis results were indicated as follows: The average genetic distance among P. aerugineum, P. purpureum and P. cruentum was 0.455. The genetic distance between P. aerugineum and P. cruentum was 0.556. The genetic distance between P. purpureum and P. cruentum was 0.396. The results show that RAPD technology can be used for genetic diversity researches in species of Porphyridium.