College of Land and Environment, Shenyang Agricultural University, Shenyang, China.
College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China.
J Sci Food Agric. 2022 Nov;102(14):6650-6657. doi: 10.1002/jsfa.12032. Epub 2022 Jun 10.
Plant growth-promoting rhizobacteria may significantly impact the soil microbial community and the growth of plant roots and have critical roles in soil ecosystem functioning. However, the interactions between rhizobacteria and plants are extremely complicated and remain understudied.
In this study, a Bacillus strain was isolated from a long-term maize colonization soil and identified as Bacillus aryabhattai strain LAD. Laboratory tests showed that B. aryabhattai LAD had phosphate-solubilizing and nitrogen-fixing functions that benefit plant growth. The effects of LAD cultures on the root system development of corn seedlings and the structure of rhizosphere bacterial communities were studied. The most significant stimulations of LAD culture on plant growth were observed at a cell density of 10 CFU mL . Treatment with LAD culture in hydroponics caused an increase of 107%, 197%, and 25% in the shoot length, total root length, and main root thickness respectively. The LAD treatment also significantly affected the rhizosphere microbial abundance and community structure. The rhizobacterial abundance and species richness in the corn seedlings treated with LAD culture were significantly lower than those in the control group. However, the LAD-treated samples had higher relative abundances of plant growth-promoting rhizobacteria like Bacillus and Burkholderia than the control samples did, suggesting that LAD treatment may facilitate the mutualistic relation between the rhizosphere microbiome and the plant.
These results collectively demonstrated that LAD is capable of shaping the rhizosphere microbial community structure and functions as a plant growth-promoting agent, which makes it a strong candidate for application as bio-fertilizer in agricultural systems. © 2022 Society of Chemical Industry.
植物促生根际细菌可能会显著影响土壤微生物群落和植物根系的生长，并在土壤生态系统功能中发挥关键作用。然而，根际细菌与植物之间的相互作用极其复杂，仍有待深入研究。
本研究从长期玉米定殖土壤中分离到一株芽孢杆菌，鉴定为芽孢杆菌 LAD。实验室试验表明，B. aryabhattai LAD 具有溶磷和固氮功能，有利于植物生长。研究了 LAD 培养物对玉米幼苗根系发育和根际细菌群落结构的影响。在细胞密度为 10 CFU mL 时，LAD 培养物对植物生长的刺激作用最为显著。在水培条件下用 LAD 培养物处理后，苗高、总根长和主根厚度分别增加了 107%、197%和 25%。LAD 处理还显著影响根际微生物丰度和群落结构。与对照组相比，LAD 处理的玉米幼苗根际细菌丰度和物种丰富度显著降低。然而，LAD 处理样本中植物促生根际细菌（如芽孢杆菌和伯克霍尔德氏菌）的相对丰度高于对照组，表明 LAD 处理可能促进了根际微生物组与植物之间的互利关系。
这些结果表明，LAD 能够塑造根际微生物群落结构和功能，作为一种植物生长促进剂，使其成为农业系统中生物肥料的有力候选物。© 2022 英国化学学会。
