中国梨属植物的分类和演化

STUDIES ON THE CLASSIFICATION AND EVOLUTION OF THE GENUS PYRUS IN CHINA

从果树进化的观点看,梨届植物大致可分为杜梨组和真梨组,前者原始后者进化。由于生态环境变化和地理隔离,梨属植物在演化过程中形成了东方梨和西方梨两大类。东方梨分布于亚洲,多数在中国;西洋梨主要在欧洲,中国引入1种。东方梨类中国有13种,豆梨为原始类型,其次是杜梨和褐梨,再次为川梨和滇梨。木梨、麻梨和河北梨为中间类型。沙梨、白梨和秋子梨是高级类型。杏叶梨是同源三倍体植物,可能是木梨的近缘种,经演化形成的次生种,新疆梨的性状界于东方梨与西洋梨之间,可能是白梨与西洋梨天然杂交后形成的次生种。

The classification and evolution of the Pyrus were studied by the authors in this present paper. From the view of evolution, the Pyrus could be divided into two sections: Sect. 1. Betulaefolia yu and Sect. 2, Pyrus yu. The section one was primeval and the section two was evolutionary. As the changes of ecology and environment and isolation of geography,the Pyrus formed two groups of east pears and west pears in the process of evolution. East pears distributed in Asia and most species in China, west pears mainly distributed in Europe, and one specie was introduced in China. There are 13 species of east pears in china. The P.calleryana, P.beulaefolia. P.phaeocarpa. P. pashia and P.pseudopashia are primitive species,the P.pyrifolia, P.bretschbeideri and P.ussueiensis are evolutionary species and the P.xerophila, P.serrulata and P. hopeiensiss are middle species between the primitive and evolutionary species. The P.armeniacaefolia is autotriploid, and may be the close relative specie or secondary specie of the P. xerophila. The character of P.sinkiangensis is between the east pears and west pears,and may be the secondary specie formed from the natural breeding specie of P.bretschyneideri with P. communis.