RhizosphericBacillus subtilisExhibits Biocontrol Effect againstRhizoctonia solaniin Pepper(Capsicum annuum)
This study aimed at evaluating the ability of SL-44 to controlRhizoctonia solaniand promote pepper(Capsicum annuum)growth. Strain SL-44 was isolated from plant rhizosphere and the pot experiment results indicated that the dry and fresh weights of pepper in SL-44 andRhizoctonia solani(S-R) treatment were 45.5% and 54.2% higher than those inRhizoctonia solani(R) treatment and 18.2% and 31.8% higher than those in CK (control, noninoculation) treatment. The plant height in S-R treatment increased by 14.2% and 9.0% compared with those in the R and CK treatments, respectively. In vitro antagonism assay showed that SL-44 exhibited strong antifungal activity against the mycelial growth ofRhizoctonia solani, with an inhibition rate of 42.3%. The amount of phosphorus dissolved by SL-44 reached 60.58 mg·L−1in broth and 7.5 μg·mL−1IAA were secreted by SL-44. Strain SL-44 inhibited the growth ofR. solaniand improved biomass of pepper plants. Mass exchange and information transmission between the pepper plants and SL-44 mutually promoted their development.Bacillus subtilisSL-44 has a great potential as biocontrol agent againstRhizoctonia solanion pepper plants.