TY JOUR TI POTATO PRODUCTIVITY DEPENDING ON THE METHOD OF APPLICATION OF GROWTH REGULATOR AND CALCULATED BACKGROUND OF MINERAL NUTRITION ON THE GRAY FOREST STEPPE SOIL OF MIDDLE VOLGA REGION KW potato KW Vineta variety KW leaf area KW leaf mass KW crop structure KW tuber yield. JO Vestnik of Kazan State Agrarian University AU Vladimirov, V.P. AU Mostyakova, A.A. AU Egorov, L.M. AU Agiev, F.F. PY 2020 IS 14 PB Kazan state agrarian University