DEVELOPMENT OF BIOTECHNOLOGICAL METHODS FOR THE MEDIUM-TERM PRESERVATION OF HOPS IN VITRO

The objective of the study is to develop effective biotechnological methods for the medium-term preservation of collection hop accessions in vitro using nutrient media, allowing for increased interpassage periods while maintaining crop viability. Research was conducted at the Altai Center for Applied Biotechnology (Altai State University, Barnaul) in 2025. The effects of glucose, mannitol, calcium nitrate (Ca(NO3)2), chlorocholine chloride (CCC), salicylic acid, abscisic acid (ABA), kanamycin, cefotaxime, and the composition of macro- and microelements in the MS nutrient medium on the medium-term preservation of five hop varieties in vitro were studied. The effectiveness of the nutrient media depends on the genotypes of the hop accessions being preserved. Media supplemented with 3.5 mg/l Ca(NO3)2 maintained the viability of regenerated Favorit and Bryansky varieties at 95 % for 12 months. On this medium, the Taurus variety demonstrated maximum viability (30 %). A 1 mg/L ABA content in the medium ensured 90–100 % survival of the crops for 6–7 months, while the Tsivilsky and Bryansky varieties had a viability of 40 % after one year of cultivation. The use of mannitol and SSS showed limited effectiveness, depending heavily on concentration and varietal characteristics. The antibiotic cefotaxime proved its potential, preserving up to 80 % of viable explants, while kanamycin proved phytotoxic and led to the death of regenerated hops. The developed protocols allow the preservation of promising hop genotypes for up to 12 months in direct culture, which is of great importance for the creation of biotechnological collections, reducing labor costs, and the commercial application of clonal micropropagation technology.