Biological control of disease complex involving Meloidogyne incognita and Rhizoctonia solani on growth of okra through microbial inoculants

A pot experiment was conducted to assess the potential role of biological control agents such as Trichoderma viride and Azotobacter chroococcum individually and concomitantly against the disease complex involving Meloidogyne incognita and Rhizoctonia solani in terms of growth and yield parameters as well as root-knot and root-rot  development on okra (Abelmoschus esculentus L.). Significant reduction was observed in root-knot and root-rot development caused by M. incognita and R. solani due to the inoculation of T. viride and A. chroococcum individually and concomitantly. The growth parameters of okra like plant length, fresh as well as dry weights, chlorophyll content, ascorbic acid content, number of fruits per plant and fruit weight per plant improved significantly due to these microbial inoculants but found more pronounced in A. chroococcum inoculated plants than T. viride treated plants. Nematode population of M. incognita was also significantly reduced in most of the treatments. This type of biological management of interacting pathogens in the rhizospheric soil proved to be a important components of organic farming. Long term application of such organic components enhanced the crop production as well as soil organic carbon for sustaining soil health. Key words: Meloidogyne incognita, Rhizoctonia solani, Disease complex, Okra, Biological control agents, Trichoderma viride, Azotobacter chroococcum.