%0 Journal Article %T Agroecological assessment of new varieties of potatoes in the middle Volga steppe %A Vladimirov, S.. %K potatoes, leaf surface, variety, yield, starch content, content of the starch, content of vitamin C, content of nitrates. %J Vestnik of Kazan State Agrarian University %D 2013 %N 8 %P 3 %I Kazan state agrarian University