Tricholoma matsutake is known to be the dominant fungal species in matsutake fruitbody neighboring (shiro) soil. To understand the mechanisms behind matsutake dominance, we studied the bacterial communities in matsutake dominant shiro soil and non-shiro soil, isolated the strains of Streptomyces from matsutake mycorrhizal root tips both from shiro soil and from the Pinus densiflora seedlings cultivated in shiro soil. Further, we investigated three Streptomyces spp. for their ability to inhibit fungal growth and Pinus densiflora seedling root elongation as well as two strains for their antifungal and antioxidative properties.Our results showed that Actinobacteria was the most abundant phylum in shiro soil. However, the differences in the Actinobacterial community composition (phylum or order level) between shiro and non-shiro soils were not significant, as indicated by PERMANOVA analyses. A genus belonging to Actinobacteria, Streptomyces, was present on the matsutake mycorrhizas, although in minority. The two antifungal assays revealed that the broths of three Streptomyces spp. had either inhibitory, neutral or promoting effects on the growth of different forest soil fungi as well as on the root elongation of the seedlings. The extracts of two strains, including one isolated from the P. densiflora seedlings, inhibited the growth of either pathogenic or ectomycorrhizal fungi. The effect depended on the medium used to cultivate the strains, but not the solvent used for the extraction. Two Streptomyces spp. showed antioxidant activity in one out of three assays used, in a ferric reducing antioxidant power assay. The observed properties seem to have several functions in matsutake shiro soil and they may contribute to the protection of the shiro area for T. matsutake dominance.

中文翻译：

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链霉菌的生物活性可能会影响松茸中白松茸的优势。

已知松茸口蘑是松茸子实体邻近（shiro）土壤中的主要真菌物种。为了了解松茸优势的机制，我们研究了松茸优势shiro土壤和非shiro土壤中的细菌群落，从shiro土壤和在shiro土壤中种植的松树幼苗中，从matsutake菌根根尖中分离了链霉菌菌株。此外，我们调查了三个链霉菌。具有抑制真菌生长和松果的能力幼苗根系伸长以及两种菌株均具有抗真菌和抗氧化特性。我们的结果表明放线菌是Shiro土壤中最丰富的门。然而，正如PERMANOVA分析所表明的，在土壤和非土壤之间，放线菌群落组成（门或阶水平）的差异并不显着。松茸菌根上存在属于放线菌属的一种，即链霉菌，尽管是少数。两种抗真菌试验显示了三个链霉菌属的肉汤。对不同森林土壤真菌的生长以及幼苗的根伸长具有抑制，中性或促进作用。两种菌株的提取物，其中一种分离自P. densiflora幼苗抑制病原性或外生菌根真菌的生长。效果取决于培养菌株的培养基，而不取决于提取所用的溶剂。两个链霉菌属。在铁还原性抗氧化能力测定中，使用的三种测定之一显示抗氧化活性。所观察到的特性似乎在松茸白土中具有多种功能，并且它们可能有助于保护松茸地区的松茸优势。