Evaluation of the effectiveness of a consortium of three plant-growth promoting rhizobacteria for biocontrol of cotton Verticillium wilt

We investigated the biocontrol efficacy of a consortium of three rhizobacteria (hereafter BBS) against cotton Verticillium wilt, along with the effect on plant growth, in a series of greenhouse and field experiments. BBS treatment inhibited germination of Verticillium dahliae spores by 88.4%. Under greenhouse conditions, BBS reduced Verticillium wilt by 86.1% compared to the untreated control, and promoted plant growth by 49.9%. In field experiments, nine L/acre of BBS suspension reduced Verticillium wilt by 76.0% and increased cotton yields by 13.7%. Soil inoculation with BBS also improved the breaking tenacity and uniformity index of harvested cotton. Soil properties improved with BBS treatment in field experiments, including an increase in organic matter and the availability of nitrogen (N), phosphorus (P) and potassium (K). There was no significant difference in the biocontrol efficacy of BBS among eight tested cotton cultivars.