Integrated Management of Root-Knot Disease of Okra Caused by Root- Knot Nematode, Meloidogyne incognita

A field study was carried out to manage the root-knot disease caused by root-knot nematode, Meloidogyne incognita infesting okra through integration of biological control agents and farm yard manure (FYM). The study site was heavily infested with root-knot nematode, M. incognita (5.3 J2s/g soil). For this study, talc-based preparation of egg parasitic fungus (fungal bio-agent), Purpureocillium lilacinum (Paecilomyces lilacinus) and plant growth promoting rhizobacteria, Pseudomonas fluorescens were applied as seed treatment (10 g/kg seed) as well as soil application (10 kg/ha) with 1.5 t/ha FYM in a Completely Randomized Block Design (CRD). Besides untreated control, chemical nematicide, carbofuran was also kept as control for comparison. Application of any of the tested management components reduced the incidence of root-knot disease of okra compared to the control (untreated). Integration of all management components caused better recovery of plant height (20%) and enhanced marketable fruit yield (71%) compared with individual treatments and/or control(s). Also, the best protection of root-knot disease of okra, in terms of reduction of root-knot gall-index (1.0) and reproductive factor (Pf/Pi (R) = 0.4), was achieved through integration of seed treatment and soil application of both bio-agents, P. lilacinum and P. fluorescens and FYM, which was recorded next to the tested chemical nematicide. It is suggested that integrated approach using bio-control agents with FYM to manage root-knot disease of okra under natural infestation is not only environmentally friendly but also more beneficial to growers. This approach has also potential for overcoming some of the efficacy problems that occur with application of individual bio-control agents.