YIELD OF POTATOES PLANT AS A FUNCTION OF IRRIGATION WATER IN THE FIELD OF KOSOVO

Water is a limiting factor to plant production (Food and Agricultural Organization,1992). Its influence on plant production can be described by the curves of growth. The data used to build the yield-water curves were collected from the plots planted with potatoes in the Field of Kosovo, in a way that the basic conditions of cultivation in each and every plot were almost the same. The only variable factor of production was the total amount of water used in irrigation for the entire period of cultivation. Having also the reaction of the production (potatoes yield) to the various amount of water, it gave us the possibility to look at the shape of the function P(V) and on this base, to determine the water volume that leads to the maximum yield and that water volume which leads to the economic potatoes yield, where the net income (profit) becomes maximal. To find out the shape of the function P(V), the regression analysis was done. After the analysis done consisted on the finding the maximum yield and the yield where the profit gets maximized. The research work presented in this paper is carried out in the Field of Kosovo, where the data about the potatoes yields and total water volumes are picked carefully from the plots under investigation. It provided enough accuracy to apply the regression analysis.