The BBCH model of seasonal growth of Cydonia oblonga Mill. in Ukraine

Phenology has not lost its relevance, especially now, when the global warming is making itself known more and more clearly. Phenological data obtained according to the BBCH system have a wide range of application: from the biological identification of global and regional weather and climate changes to the use in the selection of new cultivars of plants adapted to modern living conditions. We found out the BBCH model of phenological growth of 19 cultivars of Cydonia oblonga Mill. (Rosaceae) of the collection of the M.M. Gryshko National Botanical Garden, National Academy of Sciences of Ukraine (NBG). In the climatic conditions of Ukraine, quince goes through an entire cycle of seasonal growth. Codification of the phenological phases of growth according to the BBCH system showed that for quince, as for other fruit plants of the Rosaceae family, is characterized by eight of the ten principal stages of seasonal growth, in particular: the development of buds (principal growth stage 0: bud development), leaves (principal growth stage 1: leaf development), shoots (principal growth stage 3: shoot development), inflorescence (principal growth stage 5: inflorescence emergence), flowering (principal growth stage 6: flowering), fruit development and ripening (principal growth stage 7: fruit development; principal growth stage 8: maturity of fruit) and senescence and onset of dormancy (principal growth stage 9: senescence, beginning of dormancy). Cydonia oblonga has vegetative and vegetative-generative buds. It differs from some other fruit plants of the Rosaceae family by the specific course of the principal growth stage 5. Quince flowers are initiated from the apical meristem of one-year shoots, therefore they do not have phenophase 51, and at the stage of development 53 they are visually invisible due to the fact that they are tightly wrapped by leaves. The studied quince cultivars of the NBG collection are similar to each other in the course of most phenophases of seasonal development. The BBCH model of the seasonal growth of quince in Ukraine corresponds to two other comparable models that record the seasonal growth of this species in Spain (Murcia region) in a semi-arid Mediterranean climate with very mild winters and hot summers and Brazil (Pelotas region) in a warm tropical climate. These facts confirm the ecological plasticity of the species and its high adaptive and reproductive capacity, which can be the key to the expansion of the region of quince cultivation in Ukraine, including through the creation of industrial plantations.