Department of Biology and Geology, CITE II-B, University of Almería, Agrifood Campus of International Excellence, ceiA3, CIAIMBITAL, 04120, Almeria, Spain.
Sci Rep. 2022 Jul 31;12(1):13150. doi: 10.1038/s41598-022-17547-8.
The use of rhizobacteria provide great benefits in terms of nitrogen supply, suppression of plant diseases, or production of vitamins and phytohormones that stimulate the plant growth. At the same time, cyanobacteria can photosynthesize, fix nitrogen, synthesize substances that stimulate rhizogenesis, plant aerial growth, or even suppose an extra supply of carbon usable by heterotrophic bacteria, as well as act as biological control agents, give them an enormous value as plant growth promoters. The present study focused on the in vitro establishment of consortia using heterotrophic bacteria and cyanobacteria and the determination of their effectiveness in the development of tomato seedlings. Microbial collection was composed of 3 cyanobacteria (SAB-M612 and SAB-B866 belonging to Nostocaceae Family) and GS (unidentified cyanobacterium) and two phosphate and potassium solubilizing heterotrophic bacteria (Pseudomonas putida-BIO175 and Pantoea cypripedii-BIO175). The results revealed the influence of the culture medium, incubation time and the microbial components of each consortium in determining their success as biofertilizers. In this work, the most compatible consortia were obtained by combining the SAB-B866 and GS cyanobacteria with either of the two heterotrophic bacteria. Cyanobacteria GS promoted the growth of both rhizobacteria in vitro (increasing logarithmic units when they grew together). While Cyanobacteria SAB-B866 together with both rhizobacteria stimulated the growth of tomato seedlings in planta, leading to greater aerial development of the treated seedlings. Parameters such as fresh weight and stem diameter stood out in the plants treated with the consortia (SAB-B866 and both bacteria) compared to the untreated plants, where the values doubled. However, the increase was more discrete for the parameters stem length and number of leaves. These results suggest that the artificial formulation of microbial consortia can have positive synergistic effects on plant growth, which is of enormous agro-biotechnological interest.
根际细菌的使用在氮素供应、抑制植物病害或产生维生素和植物激素刺激植物生长方面具有巨大的益处。同时，蓝细菌可以进行光合作用，固定氮，合成刺激根发生、植物地上生长的物质，甚至可以提供可被异养细菌利用的额外碳源，并作为生物防治剂，使它们具有巨大的作为植物生长促进剂的价值。本研究集中于使用异养细菌和蓝细菌建立体外共生体，并确定它们在番茄幼苗发育中的有效性。微生物收集由 3 种蓝细菌（属于念珠藻科的 SAB-M612 和 SAB-B866 以及 SAB-B866）和 GS（未鉴定的蓝细菌）和 2 种磷钾溶磷异养细菌（假单胞菌 PUTIDA-BIO175 和 Pantoea cypripedii-BIO175）组成。结果表明，培养基、培养时间和每个共生体的微生物成分的影响决定了它们作为生物肥料的成功。在这项工作中，通过将 SAB-B866 和 GS 蓝细菌与两种异养细菌中的任何一种组合，获得了最兼容的共生体。GS 蓝细菌在体外促进了两种根际细菌的生长（当它们一起生长时，对数单位增加）。而 SAB-B866 蓝细菌与两种根际细菌一起刺激了番茄幼苗在体内的生长，导致处理过的幼苗的地上部分发育更好。与未处理的植物相比，用共生体（SAB-B866 和两种细菌）处理的植物的鲜重和茎直径等参数更为突出，其值增加了一倍。然而，对于茎长和叶片数量等参数的增加则较为离散。这些结果表明，人工配方的微生物共生体可以对植物生长产生积极的协同作用，这在农业生物技术方面具有巨大的兴趣。
