Antifungal Activity of Indigenous Microbiota for the Suppression of Red Rot of Sugarcane Under Field Conditions

Red rot caused by Colletotricum falcatum Went is a major constraint in the production of sugarcane crop. The main practice to manage red rot disease is to rely on chemical pesticides but the effectiveness is decreasing due to resistance development in pathogenic strains. This study was conducted to evaluate the efficiency of indigenous microbiota to suppress red rot of sugarcane under field conditions. A field trial was conducted with two red rot susceptible genotypes (NSG-59 and CPSG2923) with already in-vitro screened bacterial and fungal rhizospheric antagonists. The obtained data revealed that all the antagonists evaluated in the field conditions proved to suppress the red rot disease incidence and severity as compare to untreated control. Among the bacterial antagonists, Bacillus subtilis and Pseudomonas putida inhibited the red rot pathogen up to 56% by reducing the lesion size in canes. The fungal antagonists Trichoderma harzianum and Phoma herbarum also inhibited the red rot pathogen up to 52% by reducing the disease severity. By inhibiting the red rot disease, these beneficial microbial strains significantly improved the plant growth and brix percentage as compared to the untreated (control) canes. The results of this study demonstrated that native rhizospheric microbial strains exhibit the potential to inhibit the red rot disease severity under field conditions and can be promising alternatives of synthetic pesticides.