Peculiarities of adventitious root formation in stem cuttings of Black Chokeberry (Aronia melanocarpa (Michx.) Elliott)) varieties depending on the influence of biologically active substances

The article deals with the issue of accelerated propagation of black chokeberry (Aronia melanocarpa (Michx.) Elliott) cultivars using green stem cuttings. The experiments used the most popular varieties of black chokeberry for their decorative properties, for use in green building and landscape design in the soil and climatic conditions of the research area. It has been proven that the studied varieties are characterized by high vegetative productivity, which is the biological basis for root propagation, and the regeneration ability of stem cuttings depends on the biological characteristics of shoot development and the use of specific rooting conditions –optimal terms of growth and shoots development, shoot type and its metamerism, as well as on their preplant treatment with biologically active substances. It was noted that the method of green stem cuttings of black chokeberry varieties involves the cultivation of full-fledged seedlings from the shoots of the current year, as well as intraspecific similarity of rhizogenesis of stem cuttings. The comparative rooting analysis of green stem cuttings of black chokeberry varieties after treatment with biologically active substances α-NOC, β-IMC, «Stimpo» and «Regoplant» is presented. The use of optimal consumption rates of biologically active substances contributed to the acceleration of regeneration processes in cuttings, a significant increase in rooting and improvement of biometric parameters of the total number and length of adventitious roots of all branching orders in rooted cuttings harvested from different parts of the shoot of all studied varieties. It has been shown that the effect of root formation stimulation in comparison with the control variant of the experiment in the phase of active shoot growth under the influence of biologically active substances is observed in all studied types of cuttings. The data obtained in the experiment allow us to determine the best rooting ability and duration of rooting among all studied varieties. The production justification of the expediency of using the studied biologically active substances for the cultivation of root-owning seedlings of black chokeberry varieties in nurseries for the purpose of using them in green construction is given.