Influence of Inoculum Levels of Root Knot Nematodes (Meloidogyne spp.) on Tomato (Solanum lycopersicum L.)

The root knot nematodes (Meloidogyne spp.) are important group of plant parasitic nematodes which poses threat to tomato (Solanum lycopersicum L.) production. The study was conducted in shade net house located at the Agronomy Department, Faculty of Agriculture, University for Development Studies, Nyankpala from September to December, 2011 to investigate the effect of inoculum densities of root knot nematodes  on the growth of tomato cv. Pectomec and the inoculum level that will cause the highest nematode infestations. The experiment was laid out in a completely randomized design with four treatments and replicated four times. The inoculum levels were: 0, 500, 1000, and 2000 freshly hatched second stage juveniles (J 2 ) of root knot nematodes /1kg soil/pot. All pots were inoculated with root knot nematode J 2 a week after transplanting of the tomato seedlings. Data were taken on plant girth, plant height, number of leaves, root galls, nematode eggs population density and root weights (fresh and dry weights). From the results obtained, it was observed that all the inoculum levels reduced the stem girth, plant height, number of leaves, and fresh and dry root weights. Increasing the nematode inoculum level resulted in corresponding increased in number of galls and nematode population build up. The reduction in growth parameters and nematode infestations were found to be proportional to the inoculum level.