Resistance to Meloidogyne Incognita Attack Discovered in Some Common Ornamentals and the Plants Nematicidal Potentials in Celosia Agentea

Root knot nematodes are found worldwide and are known to affect over 2000 species of plants including various vegetable and crop species. Chemical control of root knot nematodes, highly effective but leads to environmental hazard because of the high toxicity and persistence of the nematicides. It is therefore part of the efforts to come up with suitable organic, human and environmental friendly alternatives that led to this investigation into the pathogenicity of the nematode on some common ornamental plants and the nematicidal potentials of their leaves in celosia argentea. The plants are Dieffenbachia bowmanii, Philodendron selleoum andMoringaoleifera. The inoculation of nematode eggs carried out on each of the plants revealed no significant defect on the plants. Their leaves were then collected, shade dried and prepared into powders following standard procedures. The leaves powder of Tageteserecta (beingnematicidal) was also prepared and used as one of the checks. The plants powders were incorporated into the soil at the rates of 5 g/kg and 10 g/kg soils at 2 weeks before transplanting of the Celosia seedlings. Carbofuran was applied at 5 g/kg soil. The 4 x 2 factorial experiment was arranged in completely randomized design (CRD) and the data analysed. The plants leaves powder exhibited significant effects on the nematodes population.