The impact of four commercial biological products on Rhizoctonia root rot disease in bean

Rhizoctonia root rot, caused by the soil-borne fungus Rhizoctonia solani, is an important disease of beans, which has been reported from different parts of Iran.The disease has been reported to cause damage to up to 60% of the crop worldwide.Biological control can be a healthy and environmentally friendly method for managing plant diseases.This study was conducted to investigate the effect of four commercial biological products available in the Iranian market on growth indices and severity of Rhizoctonia root rot in beans to find a suitable method for biological control of the disease.The effect of three biological products of arbuscular mycorrhizal fungi including Funeliformis mosseae, Rhizoglomus intraradices and Mycopersica (a mixture of several mycorrhizal fungi) and the bacterium Bradyrhizobium japonicum on growth indices and severity of Rhizoctonia root rot in Kosha pinto-bean cultivar was tested under greenhouse conditions.Statistical analysis of the data from this experiment showed that these treatments had a significant effect on reducing disease severity and plant growth indices, and among them, F. mosseae and Mycopersica caused the greatest reduction in disease severity and improved plant growth indices, respectively.Therefore, the biological product of F. mosseae and Mycopersica can be used to reduce the severity of Rhizoctonia root rot disease in beans and improve its growth indices.