可可茶种群分化及其与近缘种的亲缘关系

Phylogentic Relationship of Camellia ptilophylla Chang with Its Allied Species and Disintegration of Its Population

利用随机多态性ＤＮＡ（ＲＡＰＤ）技术对茶Ｃａｍｅｌｉａｓｉｎｅｎｓｉｓ（Ｌ）ＯＫｔｚｅ、普洱茶Ｃａｓａｍｉｃａ（Ｍａｓｔ）Ｃｈａｎｇ和可可茶ＣｐｔｉｌｏｐｈｙｌａＣｈａｎｇ含不同类型嘌呤生物碱（含可可碱、含可可碱＋咖啡碱、含咖啡碱）的３个类群进行了分析．选用１６个引物（１０ｂｐ）扩增出４０１个ＤＮＡ片段，用于遗传相似性分析，构建树系图．分析结果表明：①可可茶种群可分为含可可碱和含可可碱＋咖啡碱两个类群，而含咖啡碱性状的类群应归并到茶Ｃｓｉｎｅｎｓｉｓ（Ｌ）ＯＫｔｚｅ类；②可可茶含可可碱和含可可碱＋咖啡碱两个类群之间亲缘关系较近，来自同一起源，后者可能是由于可可茶与近缘种杂交所致；③可可茶与近缘种茶、普洱茶之间的亲缘关系较远。

Camellia ptilophylla Chang was divided into three demes: C ptilophylla 1(containing theobromine), C ptilophylla 2(containing theobromine+caffein) and C ptilophylla 3(containing caffein) The three demes and C sinensis (L )O Ktze , C assamica (Mast ) Chang were analysed, using random amplified polymorphic DNA (RAPD) genetic markers Sixteen oligonucleotide primers of arbitrary sequence (10 bp) were selected for DNA amplification,generating 401 RAPD bands were used for the analysis of genetic similarity The dendro gram was constructed by using UPGMA method from the Phylip3 752c programs based on the RAPD data The result shows that:① C ptilophylla Chang only can be divided into two demes of containing theobromine and containing theobromine+caffein The deme of containing caffein should return to the C sinensis (L )O Ktze ② The deme of containing theobromine and the deme of containing theobromine+caffein are closely related, the both have the same origin,and the latter may result from the hybridization between C ptilophylla and its allied species ③ There is a far genetic distance between C ptilophylla and C sinensis or C assamica Therefore, the opinion that C ptilophylla must be a independent species can be supported by the result of RAPD analysis