The paper emphasizes the effect of organo-mineral fertilizer application on tuber production and the content of the main mineral elements in the Semenic potato variety, under crops in the mountain region, Romania, in a rather harsh natural environment characterized by a damp and cold climate and the low quality of soils in the area. From a nutritional point of view, potato is considered a high-demand plant in terms of nutritive elements, as it forms and abundant plant mass and a high tuber quantity for the surface unit. It is a highly-consuming in nitrogen, phosphorus, potassium, magnesium and calcium, as well as microelements. The mineral element uptake in the soils for potato crop is high, thus determining the quick soil impoverishment and requiring the proper fertilization of potato crop, which is adequate to the specific management system in the mountain area. Known as the basic occupation of the locals in the area, especially in animal breeding, thus obtaining a large quantity of organic fertilizers that, through a rational employment represent the main fertilizing source for crops in the area. The cultivated assortment of crops in the area is limited to potato, lye, oat, certain fruit-trees and vegetables, while the rest of lands are covered with natural pastures and forests. For this assortment, potato shows the highest percentage, as it is an essential food product for locals and their animals, as the basic food support of people in the area. The organic matter formed in the soil on the basis of natural fertilizers positively influences the soil's physical traits, contributes to the decrease of wind and water erosion, diminishes nutrition imbalances and enhances the effect of mineral fertilizers applied to complete the necessary of nutritional elements for plants. The paper aims at a correct assessment of the organomineral fertilizer requirement on the basis of the uptake of the main nutritive elements in the soil alongside the harvests and the relevant values, agrochemical indices of the soil, towards maintaining and enhancing soil fertility in the mountain area.
