Abstract
Two field experiments were conducted in Al- Danadan potato farm in Mosul – Iraq in Spring season of 1999 and 2000, to study the effects of K fertilizer (0 and 24.5 Kg/donum), four levels of NP fertilizer (0, 50 Kg/N/donum + 31.5 Kg P/donum, 75 Kg N/donum + 47.25 Kg P/donum and 144 Kg N/donum + 47.25 Kg P/donum) and water stress (normal irrigation and no water supply till plants wilting during the period of tubers formation) on the quality of yield. The results showed better quality of yield with the addition of K and NP fertilizers, whereas plants exposure to water stress during the period of tuber formation resulted in a significant decrease in the quality of potato yield.
