The Effect of Nitrogenous Fertilizers on Nitrate, Oxalic Acid and NPK Content of Tomato (Lycopersicon Esculentum L.)

Authors: M. Rüştü KARAMAN, A. Reşit BROHİ

Abstract: The main object of this study is to investigate the effect of nitrogenous fertilizers on nitrate, oxalic acid and N,P,K content of tomato plant. This research was laid out on the Land of Agricultural Faculty during the year of 1994-95. The experiment was planned by using split plot desing with two factors and three replication. In this experiment H-2274 tomato variety was used. Nitrogen sources of ammonium nitrate ammonium sulphate, calcium ammonium nitrate, urea and potassium nitrate were used at 0, 4, 8, 16, 32 kg/N/da rates. In addition, 10 kg P205/da as TSP and 5 kg K2O/da as K2SO4 were applied for normal growth of tomato plants. According to the result of the experiment, increasing rates of nitrogen up to 32 kg N/da increased the tomato nitrate content. The lowest average nitrate content of 35.10 mg/kg was obtained at 0 kg N/da rate, whereas the maximum average nitrate content of 51.68 mg/kg was obtained at 32 kg N/da rate. The nitrate content of 40.88 mg/kg was obtained at ammonium sulphate application and the nitrate content of 46.65 mg/kg was obtained at ammonium nitrate application. The oxalic acid content of fruit, NPK content of leaf and fruit were varied with fertilizer rates and sources.

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