西藏野生油菜性状演化与分支分类研究

Study on character evolution and cladistic taxonomy of wild rapes (Brassica campestris and B.juncea) in Tibet

以西藏野生白菜型油菜(Brassica campestris L.)和野生芥菜型油菜(B.junceaCzern.et Coss.)的39个形态学性状为依据,以醉蝶花(Cleome spinosa Jacq.)为外类群,确定了性状的祖征和衍征。应用最大同步法,对35个西藏野生油菜种源的性状演化与分支分类进行了研究。结果表明,野生白菜型油菜和野生芥菜型油菜的基生叶、薹茎叶和花器官性状既有同期演化性状也有非同期演化性状;而伸长茎叶的所有性状均为非同期演化性状,有各自独特的演化规则。西藏野生白菜型油菜分为藏东野生白菜型油菜和藏中野生白菜型油菜2个组,野生芥菜型油菜分为藏中西野生芥菜型油菜和藏南野生芥菜型油菜2个组,各自沿不同的路线演化。

Thirty-nine morphological characters of wild rapes （Brassica campestris L. and B. juncea Czern. et Coss. ）in Tibet were analyzed to identify their plesiomorphies and apomorphies using Cleome spinosa Jaeq. as the outgroup. The character evolution and cladistic taxonomy of thirty-five provenances of wild rapes in Tibet were studied by the method of maximal same step length. The result showed that the evolution of some characters of basal leaf, leaf of bolting stem and flower was synchronous while the evolution of other characters was asynchronous, and the evolution of all characters of leaf of elongation stem was asynchronous with its own unique evolution regulation. The wild provenances of B. campestris in Tibet was divided into two groups, including East Tibet group and Middle Tibet group. The wild provenances of B. juncea was also divided into two different groups, including Middle-west Tibet group and South Tibet group. Every group evolved following its own evolution route.