Autogamy of polyploid apple varieties and forms

Long-term study of triploid varieties obtained from crossing of diploid varieties and forms with tetraploid ones has resulted in showing their high autogamy. In the case of natural self-pollination of the Rozhdestvenskoe triploid variety, the fruit yield was 12.6%, and that in the case of its cross-pollination with other varieties averaged only 9.55; in the Avgust triploid variety, the fruit yield was 4.4 and 2.8%, respectively. The high autogamy of tetraploid varieties and forms is evidenced by the following data: their crossing with diploid varieties (4x × 2x) yielded 4003 one-year seedlings, of which approximately 15% proved to be tetraploid.