腐生型兰科植物研究进展

腐生型兰科植物又称完全菌根异养型兰(Fully Mycoheterotrophic Orchids),无绿叶,不含叶绿素,不能进行光合作用制造有机物,完全依靠与其共生的真菌提供营养。近年来,腐生兰独特的生活方式引起了生物学家对其生理生态及进化问题的广泛关注,但目前仍缺乏系统深入的研究。为此,作者通过整理《中国植物志》和近年来报道的相关文献,发现分布在中国的腐生型兰科植物约有23属81种,主要集中在天麻属(Gastrodia)(24种)、鸟巢兰属(Neottia)(8种)、无叶兰属(Aphyllorchis)(6种)、山珊瑚属(Galeola)(5种)等。由于腐生兰特殊的营养需求,相比于其他营养类型的兰科植物,其菌根真菌有较大区别。腐生兰的菌根真菌主要有两大类,即外生菌根真菌(Ectomycorrhizal fungi,ECM)和非丝核菌类的腐生菌(Non-rhizoctonia SAP fungi)。该文还综述了腐生兰与其菌根真菌的专一性、营养来源以及系统进化等问题,提出了目前研究存在的问题,并对今后的研究工作进行了展望,以期为腐生兰的资源保护及再生研究提供参考。

Research progress of saprophytic orchids

Saprophytic orchids also called fully mycoheterotrophic orchids, without leaves and chlorophyll, losing the photosynthetic ability to create organic matter and depending entirely on mycorrhizal fungi for their supply of nutrition. In recent years, their unconventional mode of life have attracted attention of biologists in the field of physiological ecology and evolutionary. Based on collecting the Flora of China and the newest related literatures, there are 81 species in 23 genera of saprophytic orchids in China. Species fall mainly within genera such as Gastrodia (24 species), Neottia(8 species), Aphyllorchis(6 species)and Galeola(5 species). The mycorrhizal fungi of saprophytic orchids have more differences compared with other orchids bacause of their particular nutritional requirements. Numerous academic studies have shown that there are two major groups of mycorrhizal fungi of saprophytic orchids. One is ectomycorrhizal fungi, the other is non-rhizoctonia SAP fungi. In addition, the specificity between saprophytic orchids and their mycorrhizal fungi were discussed, advances on nutritional source and evolution of saprophytic orchids were summarized, the problems in current research were mentioned, as well as the future research were proposed. Overall, the review provides a reference for resources conservation and further study of saprophytic orchids.