ROLE OF CERTAIN INORGANIC FERTILIZERS ON CONTROLLING Meloidogyne incognita INFECTING TOMATO PLANTS UNDER GREENHOUSE CONDITIONS

Abstract

The role of spray application of three inorganic fertilizers MnSO4, ZnSO4 and CaCl2 at three concentration each viz: 50, 100 and 150 mg/l of the first two elements and 100, 200 and 300 mg/l for the latter fertilizer three times at one week interval in comparison with oxamyl at the recommended dose (0.39/plant) on development and reproduction of M. incognita infecting tomato plants cv. Castle Rock and plant growth was studied under greenhouse conditions (29±7ºC). Obviously all tested nutrient minerals with their concs. significantly improved plant growth parameters and reduced nematode criteria, respectively as well to great extent. Among the tested inorganic fertilizers, CaCl2 at 200 mg/l/plant overwhelmed other treatments, followed by that of MnSO4 at 150 mg/l in the increments values of plant growth parameters such as shoot dry weights (30 and 21.1%). whereas, ZnSO4 at 100 mg/l application had the lowest value (9.6%) in this respect, respectively. Similar trend was noticed regarding reduction of nematode criteria such as population density (90.8, 90.7 and 90.2%) respectively. Likewise, nematode multiplication was also affected by the tested nutrient elements performing the above trend, where CaCl2 at 200 mg/l and ZnSO4 at 50 mg/l/plant represented of minimum and maximum values that averaged 0.13 and 0.16 vs 1.39 for nematode alone respectively. N, P, K concs., chlorophyll and total phenol contents in leaves of tomato either infected with M. incognita or not as influenced by foliar spraying of the tested inorganic fertilizers were reported and discussed.