Study regarding the influence of NPK fertilizers on the total nitrogen content from tomato ( Lycopersicum esculentum )

Nitrogen is an indispensable element for plants, being the fourth element as a percentage of plants by carbon, oxygen and hydrogen, in his absence they do not develop as a result of inhibition of chlorophyll synthesis and loss of nutritional values of fruits, hence the efficiency of this element in plans fertility of all plants. Conversely nitrogen (N), plants sensitizes the fall and decreases resistance to frost, pests and drought. Tomato culture occupies a leading position in the EU population consumption, the importance of which derives from the rich content of vitamins, carbohydrates, organic acids, mineral salts (potassium more, then, iron, phosphorus, magnesium, calcium, aluminum, iodine, etc.) and energy items therefore be pursued and N content in fruits, due to the application of fertilizer nitrogen content in excess causes toxicity phenomena. The theme of the paper, it aims to conduct various types of simple and combined NPK fertilizers, applied to two types of soil: chernozem and aluviosoil in vegetation pots, on tomato crop, following their remanence in plants and production increase. NPK based fertilizers applied to tomatoes as basic fertilizer are soluble and easily assimilated by plants, dosing being correlated with soil properties and climatic conditions (BALIGAR & al.[4], DAVIDESCU [10], DORNEANU [11]). In terms of experimenting with the application of various doses of fertilizer based on NPK, no differences of values are recorded which ensure statistically compared with the control variant in the case of tomatoes, and in leaves most variants recorded very significant value, less in variants fertilized with N100P100.