Institute of Botany, Czech Academy of Sciences, Department of Mycorrhizal Symbioses, Zámek 1, 252 43, Průhonice, Czech Republic.
University of Chemistry and Technology Prague, Technická 5, 166 28, Praha 6, Czech Republic.
World J Microbiol Biotechnol. 2018 Mar 13;34(3):48. doi: 10.1007/s11274-018-2426-7.
Putative endophytes of Miscanthus × giganteus were isolated, and screened in the laboratory, greenhouse and field for their plant growth promoting properties in this host. Pantoea ananatis and Pseudomonas savastanoi were the predominant bacteria in leaves whereas other pseudomonads prevailed in roots. Almost all fungal endophytes belonged to the Pezizomycotina and most were isolated from roots; Fusarium oxysporum was most abundant, followed by the genera Periconia, Exophiala, Microdochium and Leptodontidium. All endophytic groups produced phytohormones and some bacteria also produced siderophores, solubilised P and exhibited ACC-deaminase activity in vitro. In subsequent pot experiments with pre-selected endophytes, several isolates including pseudomonads, Variovorax paradoxus, Verticillium leptobactrum, Halenospora sp. and Exophiala sp. enhanced Miscanthus growth in gamma-sterilised soil. These promising Miscanthus-derived isolates were tested either as single or mixed inocula along with a mixed bacterial inoculum originating from poplar. No significant effects of inocula were detected in a pot experiment in non-sterilised soil. On two marginal field sites the mixture of bacterial endophytes from poplar had a consistently negative effect on survival and growth of Miscanthus. Contrarily, mixtures consisting of bacteria or fungi originating from Miscanthus promoted growth of their host, especially on the heavy metals-polluted site. The combination of bacteria and fungi was inferior to the mixtures consisting of bacteria or fungi alone. Our observations indicate extensive potential of mixed bacterial and fungal endophytic inocula to promote establishment and yield of Miscanthus grown on marginal and polluted land and emphasise the necessity to test particular microbial-plant host combinations. Morphotypes of fungi isolates from Miscanthus × giganteus.
拟南芥内生菌被分离出来，并在实验室、温室和田间对其在本宿主中的促植物生长特性进行了筛选。Pantoea ananatis 和 Pseudomonas savastanoi 是叶片中的主要细菌，而其他假单胞菌则在根部占优势。几乎所有的真菌内生菌都属于 Pezizomycotina，大多数是从根部分离出来的；腐皮镰刀菌最为丰富，其次是拟青霉属、外瓶霉属、微束梗霉属和少根霉属。所有内生菌都产生植物激素，有些细菌还产生铁载体、溶解 P，并在体外表现出 ACC 脱氨酶活性。在随后的盆栽实验中，用预选的内生菌进行了实验，包括假单胞菌、多形拟杆菌、细弱拟青霉、海诺孢菌和外瓶霉在内的几个分离株在γ-灭菌土壤中促进了芒草的生长。这些有前途的芒草衍生分离株被测试为单一或混合接种，以及来自杨树的混合细菌接种。在非灭菌土壤的盆栽实验中，未检测到接种物的显著影响。在两个边缘田间地点，来自杨树的细菌内生菌混合物对芒草的存活和生长始终有负面影响。相反，来自芒草的细菌和真菌混合物促进了其宿主的生长，特别是在重金属污染的地点。细菌和真菌的混合物不如单独的细菌或真菌混合物。我们的观察表明，混合细菌和真菌内生菌接种物具有广泛的潜力，可以促进芒草在边缘和污染土地上的建立和产量，并强调了测试特定微生物-植物宿主组合的必要性。
