Estimation of the callus formation and regeneration efficiency in spring varieties of barley zoned in Ukraine

Eight commercial varieties of spring barley (Getman, Tabora, Adagio, Galaktik, Europrestige, Korona, Nevada, and Stalker) were used for the in vitro culture establishment and the development of an efficient protocol for the induction of the callus formation and plant regeneration. Mature embroys of the above-mentioned genotypes were used as explants. The induction of callus formation, culture passage, and plant regeneration were carried out using a medium containing MS salts supplemented with casein hydrolysate (1 g/l), L-proline (690 mg/l), thiamine-HCI (1 mg/l), maltose (30 g/l), 2,4-D (2 mg/l), CuSO4 (12.5 mg/l), myoinositol (250 mg/1), and gelrite (3.5 g/l) at pH 5,6–5,8. The ability of callus formation was observed in all studied varieties, and the callus formation’s frequency varied from 65 ± 3.4% to 100%. The highest regeneration potential was revealed for the Korona (88 ± 2,8%), Europrestige (89 ± 6.5%), Tabora (93 ± 3.4%), Getman (99 ± 0.8%), and Nevada (100%) varieties. For all cultivars the generation of plants from a calli occurred via the organogenesis and somatic embryogenesis. The highest total regeneration potential was registered for the Getman variety (50 ± 5%), which was selected for the further development of effective genetic transformation protocols.