Potatoes are plant with a high concentration of starch. It is distinguee for high nutritious and curative capacity with wide range of usage. Its productivity is influenced by: soil type, its fertility, technology of cultivation. Optimal bases of K 2 O (K2SO4) are primary depended by soil type as well as the parameters of technology of cultivation. The absence symptoms of potassium can be observed by a dark brown colour in leaf, curl of apex and the necrosis. Leaf fertilization is recommended when absences of potassium is very high and caused by a long dryness or grow of plant in alluvial argil soil. Traditional fertilization methods are applied. Potassium doses influence the altitude of plant, number of shoot, contents of plant residue starch and its productivity. Influence of potassium fertilization of plant potatoes was carried during the 2002-2004 period, near the IPPT (Institute of Vegetable-Potatoes in Tirana). Experiments were repeated four times in five different variants with different levels of fertilization (0, 50, 100, 150, 200 kg/ha a.s.) in soils with medium concentration of nitrogen and potassium. Was evaluated: technology of plant, penology, growth dynamics, number of shoot, number of tuber root, resistance to diseases, indication of production, economic evaluation and starch content. Based on this indication it concludes that the best recommendation doses is 150-200 kg/ha active material potassium.

potatoes; potassium fertilizer; starch; nitrogen; technology of cultivation

Presentation: oral