Characteristics of biological features of flowering and breeding evaluation of pear varieties and hybrids in the humid-subtropic zone of the Black sea coast

Abstract. The study of the biology of flowering of pear trees is important for identifying the phenological features of this period in different years, as well as for revealing the biological and adaptive potential of modern pear varieties in different regions and extreme conditions. For this purpose, it is necessary to study the relationship between the flowering process and external environmental factors, as well as to identify how pear trees react to adverse conditions during the flowering period. At the collection site of the FRC SSC of RAS pear varieties and hybrids of different ripening periods (Pyrus L.), belonging to various species, such as Pyrus communis L. (common pear), Pyrus pyrifolia (Burm.) Nakai (pear pear-leafed, syn. sandy), including interspecific hybrids (P. communis L. × P. pyrifolia). As a result of the research, varieties with early and late onset of flowering were identified. With an early start of flowering (from April 5), the varieties Sochinskaya Krupnoplodnaya, Verbena, Choo-chen-sok, Kilchu, Slavyanka, Nart were selected. Pear varieties with late flowering (April 18-23) have been identified: Williams, Starkrimson, which are of particular interest for use in breeding for breeding late-flowering varieties with increased resistance to adverse weather conditions in the spring period in the humid subtropics of southern Russia. For breeding for the multi-flowered corymb, varieties were selected: Nart, Kieffer, hybrid 2248. For breeding decorative forms with double flowers, the Nart variety and varieties with pink petals were selected: Williams Krasny, Starkrimson. Varieties Verbena, Chernomorskaya Yantarnaya, Avgustovskaya, Rassvet, Choo-chen-sok, Kilchu, Kure, Slavyanka, Red Williams and hybrids 8520, 11480 are defined as partially self-fertile, the abnormal length of the pistils (below the anther level) does not affect the pollination process. Varieties Nart and Kieffer with male sterility can be used in hybridization as a maternal form. Keywords: pear, variety, species, phenology, flowering, trait, breeding