| 摘要: |
| 【目的】探究密旋链霉菌（Streptomyces pactum）Act12 对土壤养分和微生物群落结构的影响，为Act12 应用于农业生产提供参考。【方法】选取陕西杨凌种植玉米的农田土壤为材料，采用室内培养试验，设置CK（未经Act12处理）和T（Act12 处理）2 个处理组，测定Act12在土壤中的定殖情况，分析培养30 d时CK和T组土壤pH 及养分含量，然后利用PCR扩增技术分析CK和T组土壤微生物多样性和群落组成变化。最后通过物种差异类别分析（Lefse）和网络拓扑结构分析，研究CK与T组土壤微生物群落结构差异。【结果】随着培养时间的延长，Act12含量呈先增加后降低趋势，其中培养15 d时土壤Act12含量最高，为4×106 CFU/g。与CK相比，T组土壤有效硫、有效铁、有效锰含量显著增加，增幅分别为29.45%，5.07%，9.68%；交换性钙含量显著减少7.05%。与CK相比，T组土壤微生物群落多样性无显著差异，门水平上相对丰度排前5的微生物种类未变，但占比发生了变化；属水平上相对丰度排前5的微生物种类发生了变化。Lefse结果显示，与CK相比，T组土壤贪铜菌属、变球菌属、浮微菌属等属微生物显著上调，溶杆菌属、甲基芽胞杆菌属、湖杆菌属等属微生物显著下调。微生物网络拓扑结构分析结果显示，与CK相比，T组网络模块化指数增加89.02%，明显提高了微生物系统的稳定性。【结论】密旋链霉菌Act12影响了土壤养分含量，改变微生物群落组成，并提高土壤微生物群落的稳定性，这均与Act12的次生代谢物密切相关。 |
| 关键词: 密旋链霉菌Act12 土壤养分 微生物群落结构 |
| DOI：10.13207/j.cnki.jnwafu.2025.10.014 |
| 分类号: |
| 基金项目:国家自然科学基金青年项目（31600407）；秦创源科技创新基金项目（2021ZDZX-NY-0005） |
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| Effects of Streptomyces pactum Act12 on natural soil nutrients and microbial communities |
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LIU Yi, SHI Zifan, GAO Xiaoyi, LIU Yan, GUO Qiao, LAI Hangxian
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College of Natural Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China
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| Abstract: |
| 【Objective】This research aimed to explore the effects of Streptomyces pactum Act12 on soil nutrients and microbial community structure,to provide reference for the application of Act12 in agricultural production.【Method】Farmland soil from Yangling,Shaanxi Province was selected for corn cultivation as the material and indoor cultivation experiments were conducted.Two treatment groups,CK (without Act12 treatment) and T (Act12 treatment),were set up to determine the colonization of Act12 in the soil.The soil pH and nutrient content of the CK and T groups were analyzed after 30 days of cultivation.Then,PCR amplification technology was used to analyze the changes in soil microbial diversity and community composition in the CK and T groups.Finally,the differences in soil microbial community structure between CK and T groups were studied through species differentiation category analysis and network topology analysis.【Result】With the extension of cultivation time,the content of Act12 increased first and then decreased.At the 15th day,the colony count of S.pactum in soil was the highest(4×106 CFU/g).Compared with CK,the contents of available sulfur,available iron,and available manganese of the soil in group T significantly increased by 29.45%,5.07%,and 9.68%,respectively,while the exchangeable calcium content significantly decreased by 7.05%.Compared with CK,no significant difference was observed in microbial community diversity in group T.The top 5 microbial species with the highest relative abundance at the phylum level remained unchanged,but their proportion changed.The top 5 microbial species with the highest relative abundance at the genus level also changed.The results of species difference discriminant analysis (Lefse) showed that compared with CK,the microbial genera of Cupriavidus,Alterococcus and Planctomicrobium in group T were significantly upregulated,while the microbial genera of Lysobacter,Methylobacillus,andPontibacter were significantly downregulated.The microbial network topology analysis results showed that compared with CK,the modularity index of the T group network increased by 89.02%,indicating that the stability of the microbial system was significantly improved.【Conclusion】S. pactum Act12 treatment changes soil nutrient content,alters microbial community composition,and enhances the stability of soil microbial communities,all of which are closely related to the secondary metabolites of Act12. |
| Key words: Streptomyces pactum Act12 soil nutrients microbial community structure |
