Plant growth-promoting rhizobacteria (PGPR) located in rhizobacteria soil are beneficial to plant growth and development. A PGPR strain AMCC100017 of Brevibacillus laterosporus synthesizes the plant hormone IAA in a tryptophan-dependent manner. In this study, the AMCC100017 strain was used to treat Malus robusta, an excellent natural rootstock for apple production, and assess its ability to promote growth. The fresh weight, dry weight, plant height, and lateral root growth of M. robusta were significantly increased with treatment. The presence of the AMCC100017 strain increased IAA content in M. robusta and promoted root secretion of tryptophan. Colonization of the strain in the roots allowed continuous synthesis of IAA and promoted plant growth. In addition, the photosynthetic efficiency in leaves increased after microbial treatment, and the utilization of nitrogen, zinc, iron, copper and magnesium in leaves was increased, which was conducive to photosynthesis. Interestingly, the activities of CAT and SOD, as well as the contents of ROS in plants colonized by AMCC100017 were increased compared to control plants, but the activities of POD and MDA contents were decreased. AMCC100017 strain affected the antioxidant capacity and stress resistance of plants. AMCC100017 strain increased the content of soluble protein and soluble sugar in plants, improved plant metabolic activity and stress resistance. Therefore, AMCC100017 not only increased IAA content and photosynthetic efficiency to promote M. robusta growth, but also affected plant through multiple metabolic pathways.

位于根际细菌土壤中的植物促生根际细菌（PGPR）有利于植物的生长发育。侧孢短芽孢杆菌的PGPR 菌株 AMCC100017以色氨酸依赖性方式合成植物激素 IAA。在这项研究中，AMCC100017菌株用于治疗八棱海棠，苹果生产的一种优良的天然砧木，并评估其对促进经济增长的能力。鲜重，干重，植物高度和侧根生长M.罗布斯塔与治疗均显著增加。所述AMCC100017菌株的存在增加IAA内容M.罗布斯塔促进根系分泌色氨酸。该菌株在根部的定植允许 IAA 的连续合成并促进植物生长。此外，微生物处理后叶片光合效率提高，叶片中氮、锌、铁、铜、镁的利用率增加，有利于光合作用。有趣的是，与对照植物相比，AMCC100017 定植的植物中 CAT 和 SOD 的活性以及 ROS 的含量增加，但 POD 和 MDA 含量的活性降低。AMCC100017菌株影响植物的抗氧化能力和抗逆性。AMCC100017菌株提高了植物中可溶性蛋白和可溶性糖的含量，提高了植物的代谢活性和抗逆性。所以，M.robusta生长，但也通过多种代谢途径影响植物。