玉叶金花种内性状置换的初步研究

通过对茜草科玉叶金花属植物玉叶金花传粉生物学及种内形态分化和分布特点的初步研究,发现该种的两个变种玉叶金花和白花玉叶金花在形态和生境适应上都有一定的规律。研究表明,楠藤与开黄花的玉叶金花原变种的传粉者主要是鳞翅目昆虫,而玉叶金花的白花变种的有效传粉者是膜翅目昆虫。认为变种白花玉叶金花居群的出现与同属植物楠藤的同域分布及避免相互竞争传粉者有关。白花玉叶金花变种的出现属于性状置换现象。

Character displacement in Mussaenda pubescens(Rubiaceae)

Based on the primary studies of the pollination biology,intra-species morphological differentiation and distribution of Mussaenda pubescens var.pubescens and M.pubescence var.alba,the relationships between the morphological differentiation and environmental adaptation were elucidated. Our observations indicated that the occurrence of M.pubescens var.alba was related to the sympatric distribution of M.erosa,which has yellow flowers and thus compete with M.pubescence var.pubescens for the same pollinators. Our studies suggested that M.erosa and M.pubescens var.pubescens share the same Lepidoptera pollinators,while the effective pollinators of M.pubescens var.alba are Hymenoptera. Primary conclusions could be drawn that the emergence of M.pubescens var.alba is a phenomenon of reproductive character displacement.