PURPOSEFUL HYBRIDIZATION OF KAKI PERSIMMON CULTIVARS WITH DIFFERENT PATERNAL FORMS

Kaki persimmon (Diospyros kaki), native to China, is the most economically important cultivated species of the genus Diospyros. The fruit production market imposes specific trends regarding fruit quality traits, prompting breeders to offer new cultivars for producers. FRC SSC of RAS has a collection of kaki persimmons, which includes cultivars with parthenocarpic fruiting and form female flowers. The cultivars ‘Fuyu’, ‘Geili’, ‘Zenji-Maru’ and the I-15 hybrid form both female and male flowers and are used in targeted crosses. The cultivar ‘Meader’, belonging to the species Diospyros virginiana L., forms male and female flowers, participates in hybridization as the paternal form to create winter-hardy, early-maturing forms with a high content of sugars in fruits. From 2017 to 2024, paternal and maternal forms were studied, among which cultivars with different types of fruit astringency were identified. 35 cross combinations were carried out, as a result of which 1 451 hybrid seeds were obtained, 1 017 hybrid seedlings were grown, and 242 promising forms were identified. The effective paternal form – cultivar ‘Zenji-Maru’ was recorded. In different cross combinations with its participation, the largest number of seeds was obtained, which varies from 58 to 68 pieces; this paternal form has a high viability of pollen – 69.35 %. A promising cross combination for the creation of persimmons forms PCNA with non-astringent pods – ‘Zenji-Maru’ × ‘Fuyu’ – was recorded, in which 102 seeds were obtained, 68 hybrids were grown, and 25 promising ones were identified. Remote hybrids were obtained with the participation of common persimmon cultivar ‘Meader’, which deviated towards the winter-hardy paternal form. To obtain new hybrid forms with non-astringent fruits (PCNA), the following cross combinations were identified: ‘Djiro’ × ‘Zenji-Maru’; ‘Hiakume’ × ‘ZenjiMaru’; ‘Zenji-Maru’ × ‘Zenji-Maru’; ‘Zenji-Maru’ × ‘Fuyu’; ‘Djiro’ × hybrid I-15; ‘Zenji-Maru’ × hybrid I-15.