The yield of ‘Elizabeth' potato variety depending on weather conditions and fertilizers

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%.