Improvement of clonal micropropagation procedure for Rosa L. representatives

This research is aimed at optimizing the methodology of clonal micropropagation of Rosa L. regenerants with a view to selecting optimal conditions for implementation of their morphogenetic potential on the example of Alan Titchmarsh and Princess Alexandra of Kent varieties. Experiments were conducted using the facilities of the Laboratory of Plant Biotechnology, Main Botanical Garden of the Russian Academy of Sciences, during the period of 2024–2025. Current-year shoot segments with a length of up to 1.5 cm containing vegetative buds were used as primary explants for initiation of growth and development in vitro. We developed an optimal sterilization scheme, allowing up to 91% of viable aseptic explants to be obtained. The conducted experiments revealed specific features of regeneration of Rosa L. explants in vitro, depending on the type and concentration of growth-regulating chemicals. The hormonal composition of nutrient media for cultivation of regenerant plants of different varieties at the micropropagation stage was optimized. The efficiency of using the MS nutrient medium (Murashige and Skoog, 1962) supplemented with 6-benzylaminopurine (BAP) and thidiazuron (TDZ) at concentrations of 0.5 mg/L and 0.1 mg/L, respectively, was established. The reproduction rate was 8.4.