TY JOUR TI INFLUENCE OF SOWING DATES AND SEEDING RATES ON PRODUCTIVITY OF WINTER WHEAT VARIETIES IN THE REPUBLIC OF TATARSTAN KW winter wheat (Triticum aestivum L.) KW variety KW productivity KW yield KW grain weight KW correlation JO Vestnik of Kazan State Agrarian University AU Fadeeva, I.. AU Tagirov, M.S. AU Gazizov, I.. AU Kurmakaev, F.F. PY 2020 IS 15 PB Kazan state agrarian University