滇西太保山森林公园子囊菌门虫生真菌物种多样性及其消长动态

云南及青藏高原存在着丰富的虫生真菌资源。本文选择云南省保山市省级城市森林公园太保山森林公园为研究区域, 对子囊菌门虫生真菌物种多样性及其季节消长动态开展了系统研究。在2016年每月采集土样和罹病昆虫, 分离虫生真菌菌株, 采用多基因(nrSSU, nrLSU, EF-1α, RPB1和RPB2)系统发育分析进行物种鉴定, 通过α多样性分析来研究虫生真菌的数量特征和种群消长动态。太保山森林公园子囊菌门虫生真菌全年均有分布, 共获得395个菌株, 包括3科9属24种; 优势属为虫草属(Cordyceps) (6个种199个菌株), 白僵菌属(Beauveria) (5个种80个菌株), 优势种依次为Akanthomyces sp.、Cordyceps tenuipes、C. cicadae、C. fumosorosea和Beauveria bassiana。7月菌株检出率最高(85株, 占总数的21.4%), 8月物种丰富度(15种)和多样性指数(2.35)最高。在5个优势种中, 只有Cordyceps cicadae受季节变化影响较大, 集中分布于5-9月, 7月分布最丰富(35株, 占该月菌株总数的41.2%); 其他4个种一年大部分时间(11或12个月)都能检测到。结果表明, 太保山森林公园子囊菌门虫生真菌资源丰富, 多数优势种对季节变化适应能力较强。

Species diversity and seasonal fluctuation of entomogenous fungi of Ascomycota in Taibaoshan Forest Park in western Yunnan

Yunnan Province and the Tibetan Plateau are home to a large diversity of entomogenous fungi. We selected Taibaoshan Forest Park of Baoshan City, in Yunnan to investigate the species diversity of entomogenous fungi of Ascomycota and their seasonal fluctuations throughout the year. We collected samples of soil and infected insects monthly in 2016, and the entomogenous fungal strains were isolated before multigene (nrSSU, nrLSU, EF-1α, RPB1, and RPB2) phylogenetic analyses were used to identify species. Finally we quanitifed the fluctuations throughout the year in alpha diversity. Entomogenous fungi of Ascomycota in Taibaoshan Forest Park were found through the entire year and we identified a total of 395 fungal strains, including 24 species from nine genera of three families. Cordyceps (199 strains of six species) and Beauveria (80 strains of five species) were the dominant genera. Akanthomyces sp., Cordyceps tenuipes, C. cicadae, C. fumosorosea and Beauveria bassiana were the dominant species. The detection rate of strains was the highest (85 strains, 21.4% of the total) in July, But the species richness (15 species) and Shannon-Wiener diversity index (2.35) were the highest in August. Among the five most dominant species, only C. cicadae was much affected by seasonal changes: occurring from May to September and being most prosperous in July (35 strains, 41.2% of the total strains in July). The other four species were detected through most of the year (11 or 12 months), indicating a constant abundance of entomogenous Ascomycota were abundant in Taibaoshan Forest Park, regardless of seasonal changes.