浙江榧属植物叶片变异及其分类学意义

Leaf Variation of Torreya Plants in Zhejiang and its Taxonomic Implications

榧属Torreya植物为国家保护植物,浙江现知有3种、1变种.通过对浙江榧属植物叶片长度、先端和基部形态的观察和测量,分析其变异式样,并结合其他形态性状探讨了其分类学意义.结果如下:1)叶片长度在4个分类群之间均为显著差异,但巴山榧T.fargesii和榧树T.grandis之间、九龙山榧T.grandis var.jiulongshanensis和长叶榧T.jackii之间的形象化柱状图均呈现不同程度的重叠;2)叶片先端形态在榧树、巴山榧、长叶榧3个种稳定,九龙山榧渐尖和急尖均存在,但在个体中稳定;3)叶片基部形态在所观测的4个分类群中都是稳定的;4)九龙山榧叶片长度在居群内和不同居群间均显示较大变异;5)叶片长度、先端和基部形态是有用的分类性状,并据此将九龙山榧作为种级处理.

The species of the genus Torreya are endangered and protective plants in China, and three species with one variety are recorded in Zhejiang. Based on the observation of leaf apex and base, together with the measure of leaf length, the variation patterns of these characters are analyzed, and the taxonomic significances are discussed in the present paper. The results are mainly as following： Leaf length shows all significant differences among the four taxa, while T. fargesii and T. grandis, T. grandis vat. jiulongshanensis and T. jackii are both more or less overlapped in the pictorialized column diagram. The shapes of leaf apex in T. fargesii, T. grandis and T. jacleii are all stable, while those of T. grandis vat. jiulongshanensis are acuminate or acute. The shapes of leaf base in the four taxa are all stable. Leaf length of T. grandis vat. jiulongshanensis shows considerably variable both in populations and among populations. A new combination, Torreya jiulongshanensis, is proposed here.