%0 Journal Article %T QUANTITATIVE ANALYSIS OF THE STATE AND PRESERVATION OF TEST CULTURES BIRCH THAT DIFFER BY AUTO- AND ALLOGAMY %A Isakov, I.Y. %K downy birch, silver birch, hybridization, drought tolerance, test cultures %J Actual directions of scientific researches of the XXI century: theory and practice %D 2020 %N 8 %P 5 %I FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov