Features of in vitro cloudberry shoot formation (Rubus chamaemorus L.) from the regions of Russian European North and Siberia

The aim of research is to study the effect of the composition of the culture medium and the concentration of 2-isopentyl adenine on the in vitro shoot formation of cloudberry forms collected in the northern regions of the European part of Russia and Siberia. The objects of the study are cloudberry plants of the Leningradskaya and Kondinskaya forms, collected in natural places of the Vyborg District of the Leningrad Region and the Kondinsky District of the Khanty-Mansiysk Autonomous Okrug - Yugra. The studies were carried out in 2022-2024 using generally accepted methods of microclonal propagation of plants. The number, average length and total length of microshoots per one regenerated plant were recorded. The experiment was repeated 3 times, with 10 plants each. The maximum values of the number of microshoots of cloudberry (on average 3.3-3.7 pcs.), their average length (1.6-1.8 cm) and total length (5.5-7.0 cm) were noted when growing regenerated plants in vitro on the MC culture medium. On the MS ½ culture medium, the number, average length, and total length of cloudberry microshoots in vitro were, on average, 1.4, 1.2-1.6, and 2.1-2.3 times smaller, respectively, than on the MS medium; on the MS ¼ medium, they were 2.8, 1.6-2.6, and 4.6-6.4 times smaller. An increase in the concentration of cytokinin 2-iP from 0.5 to 1.0 mg/l in the culture medium contributed to an increase in the number of cloudberry microshoots (on average, 1.3 times) in vitro culture and a decrease in their average length (2-3.2 times) and total length (2.8-3.1 times).