NEMATICIDAL POTENTIAL OF NIHORT-LYPTOL AND NIHORT-RAKTIN AGAINST ROOT-KNOT NEMATODE (MELOIDOGYNE INCOGNITA)

Abstract

The root-knot nematode, Meloidogyne incognita is one of the major limiting factors in horticultural crops production in many parts of the world including Nigeria. Efforts at managing it are targeted at using different biopesticides as alternative to nematicides which are detrimental to human health, environment and also expensive. The nematicidal potential of NIHORT-Lyptol and NIHORT-Raktin (Bio-pesticides formulated in National Horticultural Research Institute, Ibadan) was assessed against M. incognita eggs and 2nd stage juveniles in the laboratory and screen house. The NIHORT-Lyptol and NIHORT[1]raktin were diluted with distilled water at 25, 50, 70 and 100 % concentration (v/v) and 0 concentration served as control. The eggs and 2nd stage juveniles were exposed to the different concentrations at 5, 10 and 15 days at an average temperature of 29.5±2.6ºC. In the screen house the 2 lowest concentrations (25 and 50%) were applied to the cucumber seedling one week after transplant and immediately inoculation with 5000 eggs of MI and cabofuran at 1.5kg a.i/ha and 2.5kg a.i/ha served as control. The experiments were arranged in a completely randomized designed with four replicates. At 5 days after the exposure both NIHORT-Lyptol and NIHORT-Raktin caused 100% eggs hatch inhibition and 2nd stage juveniles’ mortality. In pot culture, application of NIHORT-Lyptol and NIHORT-Raktin were very effective in reducing the formation of galls, and final nematode population density in the soil and increased plant height of cucumber. Thus, NIHORT-Lyptol and NIHORT[1]Raktin are promising bio-pesticides. However, further research is needed to evaluate their efficacy under field conditions.