Efficacy of moringa (Moringa oleifera) formulations on suppression of root-knot nematodes (Meloidogyne incognita) and growth of tomato (Solanum lycopersicum)

Root-knot (Meloidogyne sp.) nematodes are among the most important causes of reduced tomato (Solanum lycopersicum) yield. Therefore, an investigation was conducted in 2022 at the Aquaculture Research Unit lab to evaluate the effectiveness of moringa (Moringa oleifera) leaf extract application in controlling root-knot nematode in tomatoes. During a survey of a tomato field, M. incognita was identified from the rhizosphere soil samples. Fresh leaf extracts of moringa, including positive control (fenamiphos 0.06), were investigated in vivo for efficacy against M. incognita in root and soil. Seedlings of tomato were inoculated with 3000 eggs and second-stage juveniles (J2s) of M. incognita in pot trials, with treatments comprising fresh leaf extracts of moringa in a series of concentrations (40 ppm-80 ppm). Fifty-six days after inoculation, the phytonematicide had reduced eggs and J2s in soil by 65-90%, gall number by 45-87%, and gall index by 35-82%. The best treatment was moringa leaf extract (80 ppm), which was significantly different (P < 0.05) from moringa leaf extract at 60 ppm and 40 ppm (P < 0.05). However, fenamiphos had no significant difference (P > 0.05). The results showed moringa leaf extract (80 ppm) was the best treatment for controlling root-knot nematode in tomatoes.