Breeding effect of selection methods (population, seed, and single-plant) at seed sites of various genetic levels in the Volgograd regionS.N. Kryuchkov, A.V. Solonkin, A.S. Solomentseva, S.A. Egorov and D.A. GorbushovaE3S Web Conf., 395 (2023) 03001DOI: https://doi.org/10.1051/e3sconf/202339503001