Evaluation of Culture Filtrate of an Entomopathogenic Bacterium for Nematicidal Properties Against Root-Knot Nematode, Meloidogyne incognita.

Bacterial culture, its culture filtrate and organic extract were tested invitro against infective juveniles (IJ) of Meloidogyne incognita . Nematicidal activity was observed in 24-96h exposure time with bacterial culture, cell free culture filtrate and organic crude extract at various concentrations. Mortality rate increased with concentration and exposure time. Bacterial culture filtrate using TSB, LB and NB media recorded 50%, 36.6% and 13.3% mortality respectively in 96h exposure time at a concentration of 150 µl/ml. Bacterial culture filtrate of TSB+Fructose exhibited nematicidal activity of 16.6% and 80% at a concentration of 150 µl/ml in 24 and 96h exposure time respectively which was higher than other media used. Organic crude extract obtained using TSB+Fructose media recorded a mortality of 70% and 100% at 2.5µg/ml and 5µg/ml concentration respectively in 24h exposure period.