三种森林生态系统昆虫病原真菌优势种生态位比较

Niche comparison of dominant entomopathogenic fungi in three forest ecosystems

研究了天然阔叶林、天然阔叶次生林和马尾松人工纯林3种不同森林生态系统中昆虫病原真菌优势种的数量组成及生态位宽度和生态位重叠值.结果表明:球孢白僵菌在这3种森林生态系统中分别为第三、第一和第二优势种.该菌在3种森林生态系统中的营养生态位宽度和时间生态位宽度均最大,远大于环链棒束孢、粉棒束孢和细脚棒束孢等优势种;该菌与其他优势种的时间生态位重叠值较大,而营养生态位重叠值较小.球孢白僵菌在3种森林生态系统中都是发生时间最长、寄主昆虫最丰富、适应环境能力最强的昆虫病原真菌.

An investigation was made on the quantitative composition,niche width,and niche overlap of dominant entomopathogenic fungi in three different forest ecosystems,i.e.,natural broad-leaved forest,natural secondary broad-leaved forest,and pure Masson＇s pine plantation.In the three forest ecosystems,Beauveria bassiana was the first dominant species in natural secondary broad-leaved forest,the second in pure Masson＇s pine plantation,and the third in natural broad-leaved forest.B.bassiana had the broadest temporal niche width and nutritional niche width,whereas the dominant species Isaria cateinannulata,I.farinose,and I.tenuipes had much smaller niche widths.Meanwhile,B.bassiana had larger temporal niche overlaps but smaller nutritional niche overlaps with other dominant entomopathogenic fungi.It was suggested that in the three forest ecosystems,B.bassiana had the longest occurrence duration,widest host range,and strongest environmental adaptability.