15个茶树品种遗传多样性的RAPD分析

Genetic Diversity of 15 Tea (Camellia sinensis (L.) O. Kuntze)Cultivars Using RAPD Markers

应用十聚体随机引物．对原产于福建、湖南、浙江、陕西、贵州、江西和湖北等省的15个无性系品种及其中2个品种的扦插繁殖后代的基因组DNA的遗传多样性进行RAPD分析，结果表明，20个随机引物在15个品种中共扩增出1050个位点．平均每个引物52．5个，每个品种70个位点。在得到的137条谱带中只有8条是所有品种共有的（单态的），129条是多态的，多态性程度达94．2％，证明了中国茶树品种资源在DNA分子水平上具有很高的遗传多样性。类平均法聚类结果表明，可将15个品种分成五个类群：A类群为江苦2号、蓝山苦茶、蓝标1号、北斗1号、福建水仙和政和大白菜等6个品种，B类群为早春早芽、乌牛早和黄叶早等3个品种，C类群为蒿坪茶、狗牯脑、大方贡茶和恩标等4个品种，汝城早芽、龙井43单独成为二个类群。从类群内多态度来看，类群B多态性最低，类群C次之，类群A最高。从类群间平均多态度和净遗传距离反映出类群A与B、B与C之间的差异程度较小且基本相似．而类群A与C之间的差异程度要大得多。

RAPD marker analyses on 15 tea cultivars and 2 cutting offsprings of them (Canlellia sinensis (L) O Kuntze) from Fujian. Hunan. Zhejiang, Shanxi, Guizhou, Jiangxi and Hubei provinces, were conducted by amplifing with 20 arbitrary 10-mer primers in order to detect the genetic diversity. Tota1 1050 loci were anlplified, with the average of 52. 5 loci per primer and 70 loci per cultivar. Only 8 bands (single-morphic)among the total 137 DNA bands were commonly appeared, 129 bands were polymorphic. The genetic diversity degree was 94. 2 %. It had been proved that Chinese tea cultivars prossessed much higher genetic diversity on DNA molecular level. These tea cultivars were divided into 5 groups by UPGMA (unweighted pair group with mathematic average ). 6 cultivars from Hunan and Fujian provinces were classified into group A, 3 cultivars from the south of Zhejiang province into group B, 4 culitivars from Shanxi, Guizhou, Jiangxi and Hubei provinces into group C. Longjing 43 and Rucheng Zaoya was belonged to 2 groups respectively. The intra-group diversity of group B was the lowest and that of group A was the highest. The inter-group diversity and net genetic distance between group A and B were smaller and shorter, and similar to those between group B and C. However, the diversity and genetic distance between A and C were much larger and longer.