TY JOUR TI SOURCES OF VALUABLE TRAITS FOR BREEDING SPRING SOFT WHEAT IN THE MIDDLE VOLGA REGION KW spring soft wheat (Triticum aestivum L.) KW breeding KW valuable trait KW genetic source KW collection nursery KW sample JO Vestnik of Kazan State Agrarian University AU Demina, E.A. AU Kincharov, A.I. AU Taranova, T.Y. AU Mullayanova, O.S. AU Chekmasova, K.Y. PY 2021 IS 15 PB Kazan state agrarian University