植物在生长过程中可能会遭受许多生物和非生物因素胁迫，从而降低生物产量. 人们已知一些植物在不同因素的刺激诱导下，能系统化建立抵抗或忍受不利因素的机制，植物根际促生菌（PGPR）就是其中一类能定殖于根系并促进植物生长的细菌.本文对PGPR促生机制进行归纳和总结，系统阐述了诱导体系抗性和诱导体系产生忍耐力两大促生机制.PGPR的作用机制的多样性暗示着其可能在更多的农业生态系统中得到应用.
Plants during their growth may suffer from many biotic and abiotic stresses, resulting in a decrease of biological production. They may also establish some mechanisms to resist or tolerate the stresses under the stimulation or induction by a variety of factors, among which, plant growth-promoting rhizobacteria (PGPR) is an important one. In this paper, the recently published papers related to this subject were reviewed, and two categories of the action mechanisms of PGPR, namely, induced systemic resistance (ISR) and induced systemic tolerance (IST), were elaborated. The diversity of the action mechanisms of PGPR implied that PGPR could be applied in more agro-ecosystems.