摘要
凋落物在生态系统中具有重要作用。为了对比凋落物内外微生物的多样性和群落结构,选取海南省海口市桂林洋海滨区3个林龄木麻黄凋落物为研究对象,采用Illumina Miseq高通量测序,对凋落物内外微生物的多样性和组成进行分析。结果表明:凋落物外生细菌的多样性高于内生细菌,中龄林凋落物内外细菌多样性和丰富度均最高,其次是幼龄林,成熟林最低。菌群群落组成分析表明:在门分类水平上,变形菌门和放线菌门最为丰富(约占总数的80%);属水平上,短小杆菌属、Jatrophihabitans、分支杆菌属、放线孢菌属、Mucilaginibacter、假单孢菌属等在不同林龄间表现出显著差异。主坐标分析(PCoA)表明,凋落物内生细菌受林龄的影响较大,而外生细菌受环境因子的影响较大;解淀粉芽孢杆菌发酵液对木麻黄种子化感潜力最强,且其中含有2,2′-亚甲基双-(4-甲基-6-叔丁基苯酚)等化感物质,表明解淀粉芽孢杆菌参与了化感物质的合成。凋落物微生物群落多样性对木麻黄的化感作用有一定影响,这为探讨微生物在木麻黄凋落物降解过程中作用的研究奠定基础。
Litter plays an important role in ecosystems.To compare the diversity and community structure of microorganisms inside and outside litter,Casuarina equisetifolia were selected from three forests in Guilin coastal area of Haikou City,Hainan Province.Illumina Miseq high-throughput sequencing was used to analyze the diversity and composition of epiphytic and endophytic bacteria of litter.The results showed that the diversity of epiphytic bacteria was higher than that of endophytic bacteria.Moreover,the diversity and richness of bacteria inside and outside C.equisetifolia litter in the intermediate-aged forest were the highest,followed by young forest and mature forest.Proteobacteria and Actinobacteria were the most abundant at the phylum level,accounting for about 80%of the total.At the genus level,Curtobacterium,Jatrophihabitans,Mycobacterium,Actinomycetospora,Mucilaginibacter and Pseudomonas showed significant variation among different forest ages.PCoA results showed that the endophytic bacteria of litter were greatly affected by forest age,while the epiphytic bacteria were greatly affected by environmental factors.The fermentation broth of Bacillus amyloliquefaciens had the strongest allelopathic potential to C.equisetifolia seeds and 2,2′-methylenebis(6-tert-butyl-4-methyl-phenol)was found in it,indicating that B.amyloliquefaciens was involved in the synthesis of allelochemicals.The diversity of litter microbial community affected the allelopathy of C.equisetifolia,which laid a foundation for studying the role of microorganisms in the degradation process of C.equisetifolia litter.
作者
张雅倩
黄蕊
左林芝
陈盼
李蕾
ZHANG Ya-qian;HUANG Rui;ZUO Lin-zhi;CHEN Pan;LI Lei(Ministry of Education Key Laboratory for Ecology of Tropical Islands,College of Life Sciences,Hainan Normal University,Haikou 571158,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2020年第7期2185-2194,共10页
Chinese Journal of Applied Ecology
基金
海南省自然科学基金项目(2018CXTD337)资助。
关键词
木麻黄
内外细菌
多样性
化感物质
凋落物降解
Casuarina equisetifolia
endophytic and epiphytic bacteria
diversity
allelochemicals
litter decomposition