Caution of intensified spread of antibiotic resistance genes by inadvertent introduction of beneficial bacteria into soil

The use of beneficial bacteria isolated especially from rhizosphere soils called plant growth-promoting rhizobacteria (PGPR) has been attracting particular interests. However, a potential source of antibiotic resistance genes (ARGs) carried by PGPRs and derived biocontrol agents and/or bio-fertilizers is widely forgotten and ignored. It is very urgent to raise the question if large-scale introduction of beneficial bacteria into soils can aggravate the situation in the spread of ARGs in environment. In this article, we conclude and analyze the possibility of a potential ARGs reservoir associated with introduction of PGPR strains into soils, and offer some advice on PGPR isolation, development and application.