ADAPTIVE POTENTIAL OF CLIMBING ROSES TO ABIOTIC STRESSORS IN HUMID SUBTROPICAL CLIMATE

The paper evaluates the adaptive potential of climbing roses to the main stressors of a humid subtropical climate using the physiological parameters of assimilation apparatus in the studied garden forms. The objects of research were represented by typical climbing rose cultivars, differing in the degree of resistance to phytopathogens – ‘Domaine de Courson’, ‘Dortmund’ (control), ‘Elegance’ and ‘Breath оf Life’. A comprehensive study of not only quantitative but also qualitative indicators of the pigment apparatus, as well as the assimilate accumulation dynamics and the antioxidant system activity made it possible to determine the plants’ physiological state and their relationship with abiotic environmental factors. The adaptability of climbing roses to abiotic factors in a humid subtropical climate is directly related to resistance to biotic stressors. Cultivars that are resistant to the effects of phytopathogens generally show great resistance to hydrothermal and insolation conditions of the region. Resistant cultivars (‘Domaine de Courson’, ‘Dortmund’) accumulate more dry matter and differ in specific leaf surface density during the growing season. They are stable in pigment content and have less enzymatic activity. Unstable to fungal diseases, climbing roses (‘Breath of Life’) are characterized by low values of certain physiological parameters, they are distinguished by high enzymatic activity both before a stressful period and in adverse environmental conditions. Against the general background, conditionally adapted cultivars (‘Elegance’), whose resistance to biotic factors varies over the years, attract attention. Such cultivars require further study with a more expanded set of physiological indicators to identify the mechanisms of their adaptation.