大小兴安岭地区红菇属物种多样性及其地理成分

红菇属(Russula)真菌广泛分布于世界各地并与多种植物根系共生形成外生菌根, 对于森林生态系统的多样性维持与群落构建具有重要的作用。我国东北大小兴安岭地区是欧亚和美洲北温带地区生物群落交流的关键地区之一, 但该地区有关外生菌根真菌的区系研究较少。本研究对采自大小兴安岭的96份红菇标本进行了形态学鉴定和ITS序列分析, 通过结合世界范围内红菇属代表性物种(146个种)的ITS序列构建了红菇属系统发育图谱。结果表明, 大小兴安岭地区红菇属有46个分类单元, 其中包括37个种和9个未定种。对大小兴安岭地区37种红菇的地理成分分析表明, 北温带分布成分有13种、温带-热带共有成分8种、欧亚成分9种、世界广布成分7种。本研究表明大小兴安岭地区的红菇具有丰富的物种多样性, 而且具有明显的北温带区系特征, 同时也具有一定的区域特殊性。

Species diversity and geographic components of Russula from the Greater and Lesser Khinggan Mountains

Russula fungi are widely distributed in the world, form ectomycorrhizae with plants, and play an important role in biodiversity maintenance and community assembly in forest ecosystems. The Greater and Lesser Khinggan Mountains of China are one of main areas in organism spreading from tropic to temperate areas in the biogeographical studies, but there are few studies on ectomycorrhizal fungi from this area. In this study, 96 specimens of Russula collected from the Greater and Lesser Khinggan Mountains were identified by the analysis of ITS sequences and morphological characters. The phylogenetic tree was reconstructed based on ITS sequences of 146 representative Russula species from China and other countries. The results showed that there were 46 taxa of Russula in the Greater and Lesser Khinggan Mountains, including 37 species and nine unidentified taxa. The analysis of geographical components of the 37 Russula species from the Greater and Lesser Khinggan Mountains showed that 13 species were north temperate, eight were temperate-tropical, nine were Eurasian, and seven were cosmopolitan. This study suggests that there are high species diversity of Russula, and their dominant components are clearly north temperate but also with some unique elements.