Qin Haichen, Wang Zixiao, Sha Wenya, Song Shuhong, Qin Fenju, Zhang Wenchao
School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou 215009, China.
Microorganisms. 2024 Mar 29;12(4):700. doi: 10.3390/microorganisms12040700.
Heavy metals migrate easily and are difficult to degrade in the soil environment, which causes serious harm to the ecological environment and human health. Thus, soil heavy metal pollution has become one of the main environmental issues of global concern. Plant-growth-promoting rhizobacteria (PGPR) is a kind of microorganism that grows around the rhizosphere and can promote plant growth and increase crop yield. PGPR can change the bioavailability of heavy metals in the rhizosphere microenvironment, increase heavy metal uptake by phytoremediation plants, and enhance the phytoremediation efficiency of heavy-metal-contaminated soils. In recent years, the number of studies on the phytoremediation efficiency of heavy-metal-contaminated soil enhanced by PGPR has increased rapidly. This paper systematically reviews the mechanisms of PGPR that promote plant growth (including nitrogen fixation, phosphorus solubilization, potassium solubilization, iron solubilization, and plant hormone secretion) and the mechanisms of PGPR that enhance plant-heavy metal interactions (including chelation, the induction of systemic resistance, and the improvement of bioavailability). Future research on PGPR should address the challenges in heavy metal removal by PGPR-assisted phytoremediation.
重金属在土壤环境中易于迁移且难以降解，这对生态环境和人类健康造成严重危害。因此，土壤重金属污染已成为全球关注的主要环境问题之一。植物根际促生细菌（PGPR）是一种生长在根际周围的微生物，能够促进植物生长并提高作物产量。PGPR可以改变根际微环境中重金属的生物有效性，增加植物修复植物对重金属的吸收，并提高重金属污染土壤的植物修复效率。近年来，关于PGPR提高重金属污染土壤植物修复效率的研究数量迅速增加。本文系统综述了PGPR促进植物生长的机制（包括固氮、解磷、解钾、解铁和植物激素分泌）以及PGPR增强植物与重金属相互作用的机制（包括螯合、诱导系统抗性和提高生物有效性）。未来关于PGPR的研究应应对PGPR辅助植物修复去除重金属方面的挑战。
