几种江蓠属海藻的ISSR标记分析

ISSR Analysis of Marine Red Algae Gracilaria (Rhodophyceae)

用ISSR标记对几种江蓠属海藻进行了遗传多样性的研究。所用的7种实验材料包括4株龙须菜(其中3株分别来自中国青岛、委内瑞拉和南非,及1株青岛产龙须菜的高温选育种)和细基江蓠繁枝变型、真江蓠、芋根江蓠。用9条ISSR引物进行筛选,有6条可扩增出清晰可辨条带。这6条引物在7种材料中共扩增出151条带,其中117条(77.48％)表现出多态性。根据Nei等的遗传相似性系数(S)对7种材料进行分析,结果显示青岛产龙须菜与其选育种的相似性最高(S为0.939)。在3株不同产地龙须菜中,青岛龙须菜与南非龙须菜的遗传距离最近(S为0.643),委内瑞拉龙须菜与前两者的S分别为0.167和0.192,因此初步推断委内瑞拉龙须菜不属于龙须菜种。包括龙须菜(产自青岛或南非)在内的4种江蓠间的相似性系数在0～0.143之间。

ISSR technique was used to investigate the genetic diversity of the genus Gracilaria (Rhodophyceae). Se ven strains of algae were analyzed, including four strains of G. lemaneiformis , three of which came from Qingdao of China, Venezuela and South Africa, respectively, and the fourth was high-temperature selected from Qingdao sample, and G. tenuistipitata var. liui, G. vermiculophylla, G. blodgettii. Of the 9 ISSR primers screened, six could produce clear bands. A total of 151 bands were amplified and 117 (77.48%) revealed polymorphism. The data were used to generate Nei's similarity coefficient (S). Results showed that G. lemaneiformis from Qingdao and its high-temperature selected strain displayed the highest genetic similarity (S = 0. 939). Among the three strains of G. lemaneiformis originated from different habitats, G. lemaneiformis from Qingdao and that from South Africa had the nearest genetic distance (S = 0. 643), while similarity coefficient of G. lemaneiformis from Venezuela with the other two was 0.167 and 0.192, respectively. So conclusion could be drawn that G. lemaneiformis from Venezuela shouldn't be ascribed to species G. lemaneiformis. The similarity coefficients between G. tenuistipitata var. liui, G. vermiculophylla, G. blodgettii and G. lemaneiformis (from Qingdao or South Africa) ranged from 0 to 0.143.