TY JOUR TI THE INFLUENCE OF CONVENTIONAL TILLAGE ON WEED INFESTATION AND YIELD OF CORN IN CROP FIVE-FIELD ROTATION KW soil minimum tillage system KW leached chernozyom KW crop contamination KW corn KW phytosanitary condition KW agrocenosis KW weeds JO Bulletin of KSAU AU Ivchenko, V.K. AU Polosina, V.A. AU Ilchenko, I.O. AU Lugantseva, M.V. PY 2018 IS PB Krasnoyarsk State Agrarian University