陆建明，黄小龙，吴文嫱，许云，夏薇，张荣萍

摘  要：为探究链霉菌30702和壳聚糖对淮山土壤微生物活性与群落的影响，采用比色法和滴定法观测土壤酶活性的变化，采用高通量测序技术和Trimmomatic等软件，分析土壤微生物群落中细菌和真菌的发展变化。结果表明，链霉菌、壳聚糖、土壤原始微生物和培养时间等4个因素对淮山土壤的脲酶和过氧化氢酶活性均有显著影响，壳聚糖浓度在0～10.0 g/kg内，土壤酶活性随壳聚糖浓度的增大而提高;随时间的延长，先升再降;壳聚糖与链霉菌之间存在交互效应。链霉菌和壳聚糖能增加淮山土壤细菌的物种丰度，减少细菌的多样性，增加艾德昂菌属（Ideonella）和纤维弧菌（Cellvibrio）等有益菌属的相对丰度，而对真菌的物种丰度和多样性的影响较小，与对照之间的差异不显著，土壤优势菌属为腐质霉属（Humicola）、枝孢属（Cladosporium）、鞘氨醇单胞菌属（Sphingomonas）和uncultured_bacterium_ c_Subgroup_6。其中，链霉菌与2.5 g/kg壳聚糖复合处理的细菌物种丰度最大，細菌多样性最少。

关键词：链霉菌;壳聚糖;淮山;土壤微生物活性;微生物群落;交互效应

中图分类号：S156      文献标识码：A

Effect of Streptomyces and Chitosan on the Soil Microbial Activities and Microbiome in Dioscorea oppositifolia L.

LU Jianming， HUANG Xiaolong， WU Wenqiang， XU Yun， XIA Wei， ZHANG Rongping*

Hainan University， Haikou， Hainan 570228， China

Abstract： In order to explore the effect of Streptomyces 30702 and chitosan on the soil microbial activity and microbiome in Dioscorea oppositifolia L.， the soil enzyme activity development was measured by colorimetric and titration methods， the change of the bacteria and fungi in soil microbiome was detected using the high-throughput sequencing technology and softwares such as Trimmomatic. The results showed that Streptomyces， chitosan， soil original microorganisms and culture time all affected the activity of urease and catalase in the soil significantly. The soil enzyme activity increased as chitosan concentration rose from 0 to 10.0 g/kg. As growing time went on， the soil enzyme activity increased first and then decreased obviously. Chitosan and Streptomyces interacted obviously. Streptomyces and chitosan increased the species abundance of soil bacteria and reduced the diversity of bacteria， increased the relative abundance of beneficial bacteria such as Ideonella and Cellvibrio， but had little effect on the species abundance and diversity of fungi and there was no significant difference between them and CK， the dominant bacteria genera in the soil were Humicola， Cladosporium， Sphingomonas and uncultured_bacterium_c_subgroup_6. Among them， the species abundance of bacteria in the Streptomyces 30702 2.5 g/kg treatment combined with chitosan was the largest， and the diversity of bacteria in the treatment was the least.

Keywords： Streptomyces sp.; chitosan; Dioscorea oppositifolia L.; soil microbial activity; soil microbiome; interaction effect

DOI： 10.3969/j.issn.1000-2561.2021.10.038

淮山（Dioscorea oppositifolia L.），又名薯蓣，为薯蓣科薯蓣属作物，单子叶缠绕性藤本植物[1]，多产于河南、山西、广东、海南等地。淮山块茎富含淀粉和各种营养成分以及Fe、Mn、Zn、Cu等丰富的微量元素及18种氨基酸，具有较高的食用和药用价值[2]。近年来随着各地政府的大力支持，我国淮山栽培面积越来越大，但淮山是忌连作作物，连作后产量下降、品质降低、病虫害加重[3]，连作第2年，一般减产20%～30%，重者甚至枯死[4]，制约了淮山产业的健康持续发展。……