SUSCEPTIBILITY OF VARIETIES AND FORMS OF APPLE TREES BY SCAB IN THE REPUBLIC OF TATARSTAN
The evaluation of scab susceptibility of leaves of apple varieties and forms in the Republic of Tatarstan is given. The average variability of susceptibility among varieties of apple scab is determined. A weak positive correlation between scab susceptibility and hydrothermal coefficient for the summer is revealed. The share of influence on the variability of scab susceptibility genotype and conditions of the year, the interaction of the genotype with the conditions of the year are determined. A weakly susceptible to scab apple varieties and forms are highlighted. An apple varieties Antonovka vulgaris, Volzhskoe, Renet Povolzhya and Arcad tenkovsky for use in breeding as the original forms and in horticulture are recommended.