摘要:
秋海棠(Begonia grandis Dry.)在我国文献记载和栽培历史悠久，具有较高的观赏、药用、食用和文化价值。该种是世界秋海棠科分布最北端、抗寒性最强及分布范围最广的少数种类之一，也是唯一地上茎叶腋产生珠芽的秋海棠属植物，因此科研价值很高。然而，有关该种的分布、资源及保护现状并不非常清楚，种下分类有待商榷。为更好地了解、保护和利用这一物种资源，本研究通过文献调查、馆藏标本查阅、野外实地考察、中国自然标本馆(CFH)、谷歌等网络活体植物照片考证等综合方法，对该种的历史、文化、分类、资源及分布、利用价值和研究进展进行了全面总结和分析讨论，并对其种下多样性进行了初步探讨。研究表明，秋海棠仅原产于中国，但在日本已经大量野生化。中国原产地分布海拔为75~3400m，最低点为江苏宜兴善卷洞，最高点为云南哈巴雪山。分布范围为东经97˚27'34''~121˚47'15''，北纬22˚59'19"~40˚40'05''，以辽宁省凌源县河坎子冰沟为最北界，云南屏边县为最南界，西藏察隅县察瓦龙秦那通为最西界，浙江宁波天童国家森林公园为最东界，较“Flora of China”记载相比，增加了重庆、广东、江苏、辽宁、天津和西藏六个省市(自治区)的分布点。近年在台湾中部山区发现该种野生植物，是原生还是自然化结果有待考证。《中国植物志》及“Flora of China”有关该种的种下单元处理均不合理，以现有的划分标准在鉴定实践中无法操作，我们正在对其种下多样性及科学分类开展综合研究。
Abstract:
Begonia grandis Dry. has a long history in cultivation and Chinese literature due to its high values as an ornamental, medicinal, edible and cultural plant. This species is the most northerly distributed, strongest cold-resistant, the only species developing tubers in leaf axils on aerial stems and one of the widest distribution taxa in Begoniaceae. Therefore, it is especially of importance in scientific research. However, the distribution, germplasm and conservation status of this species have not been well understood before, and its intraspecific classification remains questionable. In order to better understand, protect and utilize B. grandis, the history, culture, utilization, classification, distribution, germplasm diversity, intraspecific taxonomical status and research advances on this species are thoroughly investigated, summarized and discussed, through a comprehensive review on literature, specimens in worldwide herbaria, field investigation and the online living plant images of it from the websites of Chinese Natural Herbarium (CFH), Google, etc. The results show that B. grandis is only native to China but has been widely naturalized in Japan. The altitude of its native distribution is from ca. 75 mto3400 m. The lowest location is at Shanjuandong of Jangsu Prov., and the highest is Haba Snow Mountain of Yunnan Prov. The distribution longitude ranges from 97˚27'34''E to 121˚47'15''E, and the latitude from 22˚59'19''N to 40˚40'05''N. Hekanzi Binggou in Lingyuan County of Liaoning Prov. is the northern boundary, and Pingbian County of Yunnan is the southern boundary; Chawa Long Qin Nathon in Chayu County of Tibet is the most western boundary, and Tiantong National Forest Park in Ningbo of Zhejiang is the eastern boundary. It is for the first time to accurately define the native distribution boundaries and provinces of B. grandis. Comparing with records in Flora of China, six provinces (municipal cities and auto-nomous regions) were added to its distributions range, namely Chongqing, Guangdong, Jiangsu, Liaoning, Tianjin and Tibet. The wild plants of B. grandis were recently discovered in a mountain of central Taiwan, but further investigation is necessary on its native or naturalized status. It is also found that the intraspecific taxa of B. grandis are not reasonably defined based on Flora Republicae Popularis Sinicae and Flora of China, and the existing criteria don’t work in practice of identification. To solve this issue, we are conducting a comprehensive morphological and molecuar study on the intraspecific diversity and scientific classification on B. grandis.