On soddy  podzolic medium  loamy soil of the Vologda region using

fertilizers in N20P20 dose while planting caused a reliable increase in potato yield of 5.4

t/hectare in comparison with control.The potato yield received when precisely calculated

doses of fertilizers were applied increased by 10.7-15.9 t/hectare (76-114%). Mineral

fertilizer system with the maximum dose of potash fertilizers and organic mineral system

differed insignificantly in their impact on the yield of tubers.Applying fertilizers both in

minimum and precisely calculated doses increased the productivity of by-products by

41-123% in comparison with control. Applying mineral doses of fertilizers reduced the

starch content in comparison with control by 0.1-0.2% in absolute value. Precisely

calculated systems of fertilizers increased the nitrates content in comparison with

applying fertilizers only while planting (N20P20) by 36-51%. The nitrates content in

potato tubers in applying precisely calculated systems of fertilizers was about 70-78% of

maximum allowable concentration. The yield of tubers and vegetable tops substantially

depended on weather and agrotechnical conditions, by 33 and 35% respectively, mostly

on fertilizers - by 60%.