Effect of a Newly Developed Bio-Nematicide in Controlling Root-Knot (Meloidogyne incognita) of Okra (Abelmoschus esculentus)

The development of new potential pesticides is essential to manage the parasitic nematodes worldwide which hinders plant growth and yield. ‎Three preparations of a newly developed Bio-nematicide and a chemical nematicide Curaterr in eight treatments, including control, were tested against root-knot (Meloidogyne incognita) of okra. All preparations of the Bio-nematicide and Curaterr were used as side dressing. Preparations of Bio-nematicide N₀D₂, N₁D₂, and Curaterr gave better results in plant growth characters, consequently with less galling and nematode development compared with untreated control. Protective (seed coating @ 10g/kg seed) and curative (soil application @ 10g/plant and 20g/plant) significantly decrease the egg masses number and gall number/plant on okra roots. Bio-nematicide (N₀D₂) showed the best performance with the highest length of shoot and root, fresh weight of shoot and root, number and weight of fruits per plant correspondingly with decreased number of galls, egg masses, adult females and juveniles of the nematode. Negative correlation between gall numbers with shoot and root length, weight of shoot and root, and weight and numbers of fruits plant-1 indicate the positive response of the treatments on okra against the root-knot nematode. These suggest that the bionematicide formulation has nematocidal properties and would have the potential to control root-knot nematodes. Therefore, farmers could adopt it as an alternative to carbofuran or other synthetic nematicide chemicals in controlling root-knot nematode on farmlands.

Keywords: Bio-nematicide; Root-knot nematode; Okra; Treatment; Biological control.