Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland.
Appl Environ Microbiol. 2012 Dec;78(23):8191-201. doi: 10.1128/AEM.02005-12. Epub 2012 Sep 14.
The exploitation of soil ecosystem services by agricultural management strategies requires knowledge of microbial communities in different management regimes. Crop cover by no-till management protects the soil surface, reducing the risk of erosion and nutrient leaching, but might increase straw residue-borne and soilborne plant-pathogenic fungi. A cross-site study of soil microbial communities and Fusarium fungistasis was conducted on six long-term agricultural fields with no-till and moldboard-plowed treatments. Microbial communities were studied at the topsoil surface (0 to 5 cm) and bottom (10 to 20 cm) by general bacterial and actinobacterial terminal restriction fragment length polymorphism (T-RFLP) and phospholipid fatty acid (PLFA) analyses. Fusarium culmorum soil fungistasis describing soil receptivity to plant-pathogenic fungi was explored by using the surface layer method. Soil depth had a significant impact on general bacterial as well as actinobacterial communities and PLFA profiles in no-till treatment, with a clear spatial distinction of communities (P < 0.05), whereas the depth-related separation of microbial communities was not observed in plowed fields. The fungal biomass was higher in no-till surface soil than in plowed soil (P < 0.07). Soil total microbial biomass and fungal biomass correlated with fungistasis (P < 0.02 for the sum of PLFAs; P < 0.001 for PLFA 18:2ω6). Our cross-site study demonstrated that agricultural management strategies can have a major impact on soil microbial community structures, indicating that it is possible to influence the soil processes with management decisions. The interactions between plant-pathogenic fungi and soil microbial communities are multifaceted, and a high level of fungistasis could be linked to the high microbial biomass in soil but not to the specific management strategy.
农业管理策略对土壤生态系统服务的开发需要了解不同管理模式下的微生物群落。免耕管理覆盖作物可以保护土壤表面，降低侵蚀和养分淋失的风险，但可能会增加秸秆残体和土壤传播的植物病原真菌。对六个长期免耕和犁耕处理的农业田地进行了土壤微生物群落和镰刀菌抑菌作用的跨站点研究。通过通用细菌和放线菌末端限制性片段长度多态性（T-RFLP）和磷脂脂肪酸（PLFA）分析，研究了表层（0 至 5 厘米）和底层（10 至 20 厘米）的土壤微生物群落。通过表面层法探讨了描述土壤对植物病原真菌的接受能力的镰孢菌土壤抑菌作用。土壤深度对免耕处理中的通用细菌和放线菌群落以及 PLFA 图谱有显著影响，群落具有明显的空间差异（P < 0.05），而犁耕田地中未观察到与土壤深度相关的微生物群落分离。免耕表层土壤中的真菌生物量高于犁耕土壤（P < 0.07）。土壤总微生物生物量和真菌生物量与抑菌作用相关（PLFA 总和的 P < 0.02；PLFA 18:2ω6 的 P < 0.001）。我们的跨站点研究表明，农业管理策略对土壤微生物群落结构有重大影响，表明可以通过管理决策来影响土壤过程。植物病原真菌与土壤微生物群落之间的相互作用是多方面的，高水平的抑菌作用可能与土壤中高微生物生物量有关，但与特定的管理策略无关。
