Guo Huijuan, Glaeser Stefanie P, Alabid Ibrahim, Imani Jafargholi, Haghighi Hossein, Kämpfer Peter, Kogel Karl-Heinz
Institute of Phytopathology, Research Centre for BioSystems, Land Use and Nutrition, Justus-Liebig-University GiessenGiessen, Germany.
Institute of Applied Microbiology, Research Centre for BioSystems, Land Use and Nutrition, Justus-Liebig-University GiessenGiessen, Germany.
Front Microbiol. 2017 Apr 13;8:629. doi: 10.3389/fmicb.2017.00629. eCollection 2017.
(syn. , syn. "") is an endofungal bacterium of the fungal mutualist (syn. ) (Basidiomycota), which together form a tripartite Sebacinalean symbiosis with a broad range of plants. strain F4 (F4), isolated from DSM 11827, induces growth promotion and systemic resistance in cereal crops, including barley and wheat, suggesting that contributes to a successful symbiosis. Here, we studied the impact of endobacteria on the morphology and the beneficial activity of during interactions with plants. Low numbers of endobacteria were detected in the axenically grown (long term lab-cultured, lcPiri) whereas mycelia colonizing the plant root contained increased numbers of bacteria. Higher numbers of endobacteria were also found in axenic cultures of that was freshly re-isolated (riPiri) from plant roots, though numbers dropped during repeated axenic re-cultivation. Prolonged treatments of cultures with various antibiotics could not completely eliminate the bacterium, though the number of detectable endobacteria decreased significantly, resulting in partial-cured (pcPiri). pcPiri showed reduced growth in axenic cultures and poor sporulation. Consistent with this, pcPiri also showed reduced plant growth promotion and reduced systemic resistance against powdery mildew infection as compared with riPiri and lcPiri. These results are consistent with the assumption that the endobacterium improves 's fitness and thus contributes to the success of the tripartite Sebacinalean symbiosis.
（同义词： ，同义词：""）是真菌共生体 （同义词： ）（担子菌门）的一种内生真菌细菌，它们共同与多种植物形成三方Sebacinalean共生关系。从DSM 11827分离得到的 菌株F4（F4）可促进谷类作物（包括大麦和小麦）的生长并诱导其系统抗性，这表明 有助于实现成功的共生。在此，我们研究了内生细菌在与植物相互作用过程中对 的形态和有益活性的影响。在无菌培养的 （长期实验室培养，lcPiri）中检测到的内生细菌数量较少，而在定殖于植物根部的菌丝体中细菌数量增加。从植物根部新分离得到的 （riPiri）的无菌培养物中也发现了较多的内生细菌，不过在反复的无菌再培养过程中数量有所下降。用各种抗生素对 培养物进行长时间处理并不能完全消除这种细菌，尽管可检测到的内生细菌数量显著减少，从而产生了部分除菌的 （pcPiri）。pcPiri在无菌培养中生长减缓且产孢不良。与此一致的是，与riPiri和lcPiri相比，pcPiri促进植物生长的能力也减弱，对白粉病感染的系统抗性也降低。这些结果与以下假设一致，即内生细菌 提高了 的适应性，从而有助于三方Sebacinalean共生的成功。
