Nematode attack on cowpeas in Nigeria

Cowpeas are attacked by 24species of nematodes distributed among 15 general. Fifteen of these 24 species of plant-parasitic nematodes have been founding Nigeria. The most destructive on local cowpea are three species of the root-knot nematode. The root-knot nematodes are also the most wide spreading Nigeria being found abundantly in all states. The reinform nematode has also been proved capable of reducing cowpea yields in Nigeria and is widely distributed. Both kinds of nematode scan cause yield reductions of 20 to 30percent.Thelife cycles of the root-knot nematodes and the reniform nematode have been studied for Nigeria and are essentially the same as reported in the literature for other tropical countries

The effects of rotation crops on survival of root-knot, root-lesion and spiral nematodes: efecto de rotacion de cosechas sobre la supervivencia de nematodos noduladores, lesionadores y espiraliformes

Potential rotation crops for replacement of natural soil regeneration in tropical agriculture were grown in nematode infested soil following Celosia argeniea. The aggregate nematode population mean was one-third the preplant mean after six months. Meloidogyne incognita juvenile soil populations were reduced under 15 crops and maintained under three. Helicotylenchus pseudorobustus populations were reduced under eight crops and maintained under 10. Pratylenchus sefaensis were maintained under 17 crops and significantly increased under Crotalaria juncea

Control of Helicotylenchus multicinctus and Meloidogyne javanica in established plantain and nematode survival as influenced by rainfall: Combate de helicotylenchus multicinctus y meloidogyne javanica en platano y el efecto de la lluvia sobre la supervivencia de nematodos

Soil treatment with oxamyl and carbofuran at 3 g followed by 1.2 g a.i./plant after 4 months reduced damage caused by Helicotylenchus multicinctus and Meloidogyne javanica to established plantain (Musa AAB). Treatment appreciably reduced nematode populations and significantly increased vigor and yield of plantain. Oxamyl gave the best response followed by carbofuran increasing yields by 98 and 61% respectively. One liquid formulation of oxamyl applied to foliage gave less nematode control and less yield than the granular formulation. In nontreated soils both H. multicinctus and M. javanica juveniles increased or decreased with rainfall. Population densities of both pathogens were significantly correlated with average and/or total rainfall but not correlated with number of rain days. Drought conditions adversely affected M. javanica juveniles populations more than populations of H. multicinctus