Streptomyces spp. perform vital roles in natural and agricultural soil ecosystems including in decomposition and nutrient cycling, promotion of plant growth and fitness, and plant disease suppression. Streptomyces densities can vary across the landscape, and inhibitory phenotypes are often a result of selection mediated by microbial competitive interactions in soil communities. Diverse environmental factors, including those specific to habitat, are likely to determine microbial densities in the soil and the outcomes of microbial species interactions. Here, we characterized indigenous Streptomyces densities and inhibitory phenotypes from soil samples (n = 82) collected in 6 distinct habitats across the Cedar Creek Ecosystem Science Reserve (CCESR; agricultural, prairie, savanna, wetland, wet-woodland, and forest). Significant variation in Streptomyces density and the frequency of antagonistic Streptomyces were observed among habitats. There was also significant variation in soil chemical properties among habitats, including percent carbon, percent nitrogen, available phosphorus, extractable potassium, and pH. Density and frequency of antagonists were significantly correlated with one or more environmental parameters across all habitats, though relationships with some parameters differed among habitats. In addition, we found that habitat rather than spatial proximity was a better predictor of variation in Streptomyces density and inhibitory phenotypes. Moreover, habitats least conducive for Streptomyces growth and proliferation, as determined by population density, had increased frequencies of inhibitory phenotypes. Identifying environmental parameters that structure variation in density and frequency of antagonistic Streptomyces can provide insight for determining factors that mediate selection for inhibitory phenotypes across the landscape.

中文翻译：

---

土著链霉菌属物种的密度和抑制表型。各地和农业生境都不同。

链霉菌 在自然和农业土壤生态系统中发挥重要作用，包括分解和养分循环，促进植物生长和适应性以及抑制植物病害。链霉菌的密度可以在整个景观中变化，抑制性表型通常是土壤群落中微生物竞争相互作用介导的选择结果。各种环境因素，包括特定于栖息地的环境因素，可能会决定土壤中的微生物密度以及微生物物种相互作用的结果。在这里，我们从在整个Cedar Creek生态系统科学保护区（CCESR；农业，草原，热带稀树草原，湿地，湿地和森林）的6个不同生境中收集的土壤样品（n = 82）中表征了土著链霉菌的密度和抑制表型。在生境中观察到链霉菌密度和拮抗链霉菌的频率有显着变化。生境之间的土壤化学性质也存在显着差异，包括碳百分比，氮百分比，有效磷，可提取钾和pH。拮抗剂的密度和频率与所有生境中的一个或多个环境参数显着相关，尽管生境中与某些参数的关系不同。此外，我们发现，生境而不是空间接近性是链霉菌密度和抑制表型变化的更好预测指标。此外，根据种群密度确定，最不利于链霉菌生长和增殖的栖息地的抑制表型频率增加。