广西3科植物内生拟盘多毛孢多样性

Diversity of endophytic Pestalotiopsis associated with three plant families in Guangxi

为进一步了解植物内生拟盘多毛孢(Pestalotiopsis)的组成及变化规律,本研究对广西林科院植物园的壳斗科(10种)、樟科(7种)和棕榈科(5种)植物的内生真菌拟盘多毛孢多样性分四季进行了调查。经分离鉴定得拟盘多毛孢属真菌30种,其中从壳斗科分离到17种、樟科分离到19种、棕榈科分离到17种,优势种为小孢拟盘多毛孢(P.microspora)。从壳斗科的饭甑青冈(Cyclobalanopsis fleuryi),樟科的樟树(Cinnamomum camphora)和棕榈科的香桄榔(Arenga engleri)中分离得到的拟盘多毛孢种数分别为8、12和12种,这3种植物分别是3科中内生拟盘多毛孢定殖种类最多的代表物种;其中樟树内生拟盘多毛孢定殖率最高(6.67%)。除棕榈科植物软叶针葵(Phoenix roebelenii)外,内生拟盘多毛孢在植物枝条中的定殖率均高于叶片,而且这些植物枝条中内生拟盘多毛孢物种多样性更加丰富。春夏秋冬四季分离得到内生拟盘多毛孢分别为18、16、12和10种;定殖率分别为3.44%、1.53%、1.10%和1.75%;物种多样性指数分别为2.5006、2.2902、2.2475和1.9541。本研究表明拟盘多毛孢偏好在某些植物种类中定殖,并有明显的组织选择偏向性,且定殖率有季节差异性。

To understand diversity and successional changes of endophytic Pestalotiopsis in plant communi- ties, we completed surveys of endophytic Pestalotiopsis in plants belonging to the Fagaceae （10 species）, Lauraceae （7 species）, and Palmae （5 species） in the Botanical Garden of Guangxi Academy of Foresty Sci- ences. We identified 30 endophytic Pestalotiopsis species, of which 17, 19, and 17 endophytic Pestalotiopsis species were obtained from Fagaceae, Lauraceae and Palmae, respectively, with Pestalotiopsis microspora as the dominant species. We collected a total of 8, 12 and 12 endophytic Pestalotiopsis species from Cyclobalanopsis fleuryi （Fagaceae）, Cinnamomum camphora （Lauraceae）, and Arenga engleri （Palmae）, respectively. We found the highest colonization frequency （6.67%） of Pestalotiopsis in Cinnarnomum camphora. We also found that colonization frequencies of endophytic Pestalotiopsis were higher on twig tissues compared with leaf tissues for most plant species except Phoenix roebelenii. The total number of Pestalotiopsis species varied by season, with 18, 16, 12, and 10 endophytic Pestalotiopsis species collected in spring, summer, autumn, and winter, respectively. Colonization frequencies of endophytic Pestalotiopsis also varied by season with frequencies of 3.44%, 1.53%, 1.10% and 1.75% in spring, summer, autumn, and winter, respectively. This research showed that Pestalotiopsis had a preference for colonization in some plants and certain tissues, and its colonization frequencies fluctuated in different seasons.