Plant Regeneration from Unpollinated Ovules of Sugar Beet (Beta vulgaris L.) on Growing Media with Different Carbohydrates

Sugar beet (Beta vulgaris L.) is referred to as a strategic species due to its exceptional economic and functional importance. Sugar beet is cultivated in order to provide material for sugar production as it is the world’s second source after sugar cane. However, in this species, the regeneration of haploid shoots is difficult in comparison to other cultures or isolated microspores. Haploid plants of sugar beet can be derived from in vitro culture mostly via gynogenesis. Therefore, the aim of this research has been to increase the effectiveness of shoot formation from unpollinated sugar beet ovules by optimising the regeneration technique via induced gynogenesis. Various types and concentrations of chosen carbohydrates in media were evaluated. The Murashige and Skoog medium containing 4.4 μmol/L of 6-benzylaminopurine was solidified by 0.7% of agar and enriched with either sucrose (0.06 mol/L or 0.09 mol/L), glucose (0.09 mol/L), fructose (0.09 mol/L), maltose (0.09 mol/L) or with a combination of sucrose (0.04 mol/L) and mannitol (0.04 mol/L) or with sucrose (0.04 mol/L) and fructose (0.04 mol/L). The control medium contained 0.09 mol/L sucrose without any cytokinins. Of all the analysed media, the best for shoot regeneration turned out to be the media with 4.4 µmol/L 6-benzylaminopurine, solidified with 0.7% agar, additionally containing 0.09 mol/L glucose or 0.06 mol/L sucrose. On those media, over three-fold more shoots compared with the control medium were produced.