南方果园蚁巢土壤微生物群落结构特征分析

【目的】探究南方果园蚁巢土壤中特有的微生物资源及其功能，为探寻功能微生物资源及南方果园土壤的生态管理提供理论依据和技术支撑。【方法】以南方荔枝园中日本弓背蚁（Camponotus japonicus）的蚁巢土壤和非蚁巢土壤为研究对象，采用高通量测序技术，分析蚁巢和非蚁巢土壤微生物群落的结构特征。【结果】蚂蚁筑巢虽然对果园土壤微生物多样性及丰富度无显著影响（P>0.05），但明显改变了果园土壤中细菌和真菌群落的组成与占比。蓝细菌门（Cyanobacteria）和WPS-2细菌是蚁巢土壤特有的优势细菌门，但缺失了芽单胞菌门（Gemmatimonadetes）、拟杆菌门（Bacteroidetes）和疣微菌门（Verrucomicrobia）等非蚁巢土壤中拥有的优势细菌门类；同时，与非蚁巢土壤相比，蚁巢土壤中变形杆菌门（Proteobacteria）和酸杆菌门（Acidobacteria）细菌丰度占比下降，放线菌门（Actinobacteria）和绿弯菌门（Chloroflexi）细菌丰度占比提高。蚁巢土壤虽然拥有与非蚁巢土壤完全一致的门类水平真菌群落组成，均由子囊菌门（Ascomycota）、担子菌门（Basidiomycota）、被孢霉门（Mortierellomycota）和unclassified_k__Fungi门组成，但优势菌门组成丰度占比发生变化，其中，蚁巢土壤中被孢霉门真菌丰度占比下降，而unclassified_k__Fungi门真菌丰度占比增加。Conexibacter、unclassified_f__Ktedonobacteraceae、norank_o__B12-WMSP1、norank_p__WPS-2、norank_o__Chloroplast、分枝杆菌属（Mycobacterium）、FCPS473、鞘氨醇单胞菌属（Sphingomonas）、norank_f__JG30-KF-CM45、间孢囊菌属（unclassified_f__Intrasporangiaceae）和中华单胞菌属（Sinomonas）是蚁巢土壤中特有的优势细菌属；瘦脐菇属（Rickenella）、节丛孢属（Arthrobotrys）、梨孢霉属（Coniosporium）、unclassified_c__Eurotiomycetes、粗糙孔菌属（Trechispora）、unclassified_o__Pezizales、unclassified_o__Pleosporales、Xepicula、茎点霉属（Phoma）和曲霉属（Aspergillus）是蚁巢土壤中特有的优势真菌属。【结论】蚁巢土壤中蕴含着丰富的具有分泌抗生素和生物修复功能的微生物资源，是一个潜在的生物资源宝藏。

Characteristics of soil microbial community structure in ant nests in orchards in southern China

【Objective】To explore the specific microorganisms and theirfunctionsin ant nests inorchards insouthern China, and provide the theoretical basis for seraching fuctional microorganism resourcesandsoil ecological management in orchards in southern China.【Method】Soil samples, which collected from ant nests(AN) of Camponotus japonicus and non-ant nests(CK) inlychee garden in southern China, their characteristics of microbial community structures were analyzed using high-throughput sequencing technology.【Result】Even though the microbial diversity and richness in soils of ant nests were not significantly affected by ant nest formation(P>0.05), the composition and proportion of bacteria and fungi in soils of ant nests were changed. Cyanobacteria and WPS-2 were the unique dominant bacterial phyla in soils of ant nests;by contrast, Gemmatimonadetes, Bacteroidetes and Verrucomicrobia were the specific dominant phyla in soils of non-ant nests. Moreover, compared to the non-ant nest, the proportions of soil bacteria at phylum level, such as Proteobacteria and Acidobacteria decreased, but Actinobac teria and Chloroflexi increased in soils of ant nests. In addition, the composition of fungi at phylum level was the samein soils between ant nests and non-ant nests, they were all formed with Ascomycota, Basidiomycota, Mortierellomycota and unclassified_k__Fungi. However, their proportions and abundances were changed in soils of ant nests which compared to non-ant nests. For example, compared to the soils of non-ant nests, the percentages of Mortierellomy cota decreased, but the unclassified_k__Fungi increased at phylum level in soils of ant nests. Meanwhile, Conexibacter, unclassified_f__Ktedonobacteraceae, norank_o__B12-WMSP1, norank_p__WPS-2, norank_o__Chloroplast, Mycobacterium, FCPS473, Sphingomonas, norank_f__JG30-KF-CM45, unclassified_f__Intrasporangiaceae and Sinomonas were the unique dominant bacteria, and Rickenella, Arthrobotrys, Coniosporium, unclassified_c__Eurotiomycetes, Trechispora, unclassified_o__Pezizales, unclassified_o__Pleosporales, Xepicula, Phoma, Aspergillus were the specific dominant fungi in soils of ant nests at genus level, respectively.【Conclusion】The abundant resources of benefit microorganisms, which have the functions of excretion of antibiotics and bio-remediation all can be found and accumulated in soils of ant nests. It suggests that the soil of ant nests is a potential treasure of biological resources.