The history of selection of ivy cultivars. I
Unlike most other cultivated plants that undergo targeted hybridization, the selection of ivy (Hedera L.) is associated with the revealing, sampling, and fixing spontaneous vegetative mutations called sports. Vegetative, or somatic mutations occur rather rarely - not more often than once a decade in about half of the ivy varieties in case of absence of pruning. In addition to original mutations, which can later become new cultivars, there are reversions, or back mutations, with traits of ancestral cultivars. Besides, there are repeated mutations, which result in duplication of traits of existing cultivars. The authors studied reverse and repeated mutations of a number of common ivy cultivars (Hedera helix L.) in order to find out their previously unknown ancestral cultivars. As a result of comparative morphological studies of the respective sports, it was found out that the cultivar 'Very Merry' (described in 1995) originated from the cultivar 'Spinosa' (described in 1974), the cultivar 'Icicle' (described in 2007) - from ' Milky Way' (described in 1996), the cultivar 'Diana's Pleasure' (described in 1999) - from 'Hester' (described in 1994).The data obtained contribute to the history of ivy cultivar selection, which has plenty lacunae, and also enrich ideas about changes in traits that occur during sports formation in ivy. Moreover, the results of the research expand the possibilities for studying the patterns of evolutionary morphogenesis under artificial selection.