Evaluation of nematicidal potential of leaves extract of Afrohybanthus enneaspermus for management of Meliodogyne incognita in Tomato

The resistance of nematode pests to synthetic nematicides and its attendant hazards both to the crops and the ecosystem have caused growing interest. This study is aimed at investigating the nematicidal potential of the leaves extract of Afrohybanthus enneaspermus. Afrohybanthus enneaspermus is an evegreen shrub found in the tropical regions. The herbs have been used in ethonomedicine in the treatment of various ailments such as fever, diabetes, cough, skin infections and so on. According to standard methods in this study, in-vivo and In-vitro nematicidal screening of leaves extract was carried out against juvenile nematode pest (Meliodogyne incognita) while the pot experiment was carried out on tomato plants infected with root knot nematode. At the growth rate of the Tomato (Tropimech +), plant height was significantly lowered at 4 WAP (four weeks after planting) in tomato plants inoculated with 2,000 root-knot nematodes (RKN) applied with 20 g powered of Afrohybanthus enneaspermus compared with the rest of the treatments. With the application of 15% aqueous plant extracts and the inoculation of 2,000 RKN, plant height was significantly higher (32.8), followed by Plant alone and 20% aqueous plant extract. However, plant height was significantly lowered in plants applied with 20g powered of Afrohybanthus enneaspermus and nematode compared to the other treatments. At 6 weeks plant height is significantly higher in tomato plants inoculated with 5% aqueous plant extract with 2000RKN followed by others that are at the same range except 20g powered extract with 2000RKN that is significantly lowered . At 7 weeks plant height is significantly higher in tomato plants inoculated with 5% aqueous plant extract with 2000 RKN followed by others that are at the same range except 20g powdered extract with 2000 RKN that is significantly lowered. The research concluded that leaves extract of Afrohybanthus enneaspermus is effective in management of root Knot nematodes, however, in- vitro experiments, it is established that the powder form of the leave has higher effectiveness in management of nematode than its organic extract.