赤星病发生期不同成熟度烟叶叶际微生物代谢与群落结构

Metabolic and Microbial Community Structure Analysis in the Phyllosphere of Tobacco Leaves with Different Maturity during Brown Spot Occurring Season

为了解不同成熟度烟叶叶际微生物在代谢功能与群落组成上的差异,采用Biolog ECO代谢表型及高通量测序技术研究了赤星病发生期不同成熟度(成熟、适熟、未熟)烟叶叶际微生物代谢功能与群落结构。结果表明,3种成熟度烟叶叶际微生物在代谢功能上存在较大差异,成熟烟叶叶际微生物代谢活性最强,其次依次为适熟、未熟烟叶,其中均能高效代谢的碳源为L-天冬酰胺酸,均一般或弱代谢的碳源为2-羟基苯甲酸、L-苯基丙氨酸、α-环式糊精、γ-羟基丁酸和苯乙基胺。3种烟叶叶际优势真菌、细菌菌门均分别为子囊菌门和变形菌门,优势真菌属均为链格孢属、枝孢霉属、亚隔孢壳属和Symmetrospora,优势细菌属均为假单胞菌属和鞘氨醇单胞菌属。3种烟叶叶际真菌中,成熟烟叶叶际子囊菌门和担子菌门相对丰度最高,且均显著高于未熟烟叶;3种烟叶叶际细菌中,未熟烟叶的变形菌门相对丰度最高,且显著高于适熟烟叶。3种成熟度烟叶真菌群落和细菌群落在多样性(Shannon、Simpson)上均无显著性差异,但成熟烟叶叶际真菌群落丰富度(ACE)最高,其次依次为适熟、未熟烟叶,且成熟烟叶显著高于未熟烟叶。

This study was conducted to investigate the differences of metabolic function and community composition in the phyllosphere of tobacco brown spot leaves at different maturity stages.The technologies of Biolog ECO metabolic phenotype and high-throughput sequencing were used to analyze three different maturity level tobacco leaves(mature,proper,immaturate)during brown spot occurring season.The results showed there were significant differences in the metabolic functions of tobacco phyllosphere microorganisms from three different maturity tobacco leaves.The highest metabolic activity was found in phyllosphere miroorganism from mature tobacco leaves,followed by the proper and immaturate tobacco leaves.L-Asparagine was the only carbon source that could be effectively metabolized in all three kinds leaf samples,while 2-Hydroxybenzoic Acid,L-Phenylalanine,α-Cyclodextrin,γ-Hydroxybutyric Acid and Phenylethylamine were all moderately or poorly metabolized in the three maturity leaves samples.The dominant phyla of fungi and bacterium of tobacco leaves at three maturity stages were Ascomycota and Proteobacteria,respectively.The dominant fungal genera were Alternaria,Cladosporium,Didymella and Symmetrospora,and the dominant bacterial genera were Pseudomonas and Sphingomonas.Among the three kinds of tobacco phyllosphere fungi,the relative abundance of Ascomycota and Basidiomycota in mature tobacco leaves was the highest,and the relative abundance of mature tobacco leaves was significantly higher than that of immature tobacco leaves.Among the three kinds of tobacco phyllosphere bacteria,the relative abundance of Proteobacteria in immature tobacco leaves was the highest and significantly higher than that in proper tobacco leaves.There were no significant differences in fungal community diversity and bacterial community diversity(Shannon,Simpson)for phyllosphere microorganisms between tobacco leaves at different maturity stages.However,the phyllosphere fungal community richness(ACE)of mature tobacco leaves was the highest,followed by that of proper and immaturate tobacco leaves,and the ACE of mature tobacco leaves was significantly higher than that of immature tobacco leaves.