于凯悦 李唯一 刘宇航 董爱荣 刘薇

摘 要：本文采用高通量测序法，探究短密木霉（Trichoderma brevicompactum）、大豆和咪唑乙烟酸三者分别处理以及共同作用对土壤细菌多样性和群落结构的影响。试验以不含上述3种物质的土壤为阴性对照。结果表明：5个不同处理样品共含有36 336个细菌OTU（operational taxonomic unit），其中共有的细菌种类有1 031个，仅占样品细菌总数的2.84%;不同处理土壤样品的细菌多样性均发生变化，短密木霉、大豆对土壤细菌多样性的影响小于咪唑乙烟酸;不同处理样品的细菌群落结构组成基本相同，差异较大的是相对丰度。变形菌门（Proteobacteria）是5个样品中的优势细菌，平均丰度为50.82%;在属的水平下，鞘氨醇单胞菌属（Sphingomonas）是5个样品中的优势细菌，其次是芽单胞菌属（Gemmatimonas）和微小杆菌属（Exiguobacterium）。结论：土壤中加入短密木霉后，土壤细菌多样性及物种总数略微下降;种植大豆后，土壤细菌多样性及物种总数升高;加入咪唑乙烟酸后，土壤细菌多样性及物种总數显著降低;短密木霉及大豆对土壤细菌多样性及物种总数的影响小于咪唑乙烟酸。

关键词：高通量测序法;短密木霉;咪唑乙烟酸;大豆;多样性

Abstract：In this paper， high-throughput sequencing was used to investigate the effects of the interactions between Trichoderma brevicompactum， soybean and imazethapyr on soil bacterial diversity and community structure. The soil without the above three substances was used as the negative control. The results showed that： five different treatment samples contained a total of 36 336 bacterial OTUs， of which 1 031 were bacterial species presented in all samples， accounting for only 2.84% of the total bacteria. The bacterial diversity of soil samples under different treatments had changed， and the effect of T. brevicompactum and soybean on soil bacterial diversity was less than that of imazethapyr. The composition of the bacterial community structure was basically the same in different treatment samples， but the relative abundance was very different. Proteobacteria was the dominant bacteria in five samples， with an average abundance of 50.82%; at the genus level， Sphingomonas was the predominant bacterium in the five samples， followed by Gemmatimonas and Exiguobacterium. Conclusion： After adding T. brevicompactum to the soil， the soil bacterial diversity and total species decreased slightly; after planting soybeans， the soil bacterial diversity and total species increased; after adding imazethapyr， the soil bacterial diversity and total species decreased significantly; the effects of T. brevicompactum and soybean on soil bacterial diversity and total species were less than that of imazethapyr.

Keywords：High-throughput sequencing; Trichoderma brevicompactum; imazethapyr; soybean; diversity

0 引言

随着农业技术的不断发展，农药的运用逐渐增多，其中，咪唑乙烟酸具有活性高、用量低和选择性广等优点，在农业市场中占有重要地位[1]，常用于大豆和苜蓿等豆科作物防除众多一年生和多年生禾本科杂草及阔叶杂草[2]。咪唑乙烟酸可以在大豆体内快速分解，半衰期仅1～6 d，但其残留期较长，在施用后3 a内不可种植除大豆以外的作物，尤其以经济作物，如紫苏、白菜、小麦和甘蔗等最为敏感，会对后茬农作物种植产生严重影响[3]，还可能残留于地下水中，对人们的生活用水造成一定的影响[4]。……