ENHANCEMENT OF PLANT-REGENERATION FROM EMBRYOGENIC CALLUS OF COMMERCIAL BARLEY CULTIVARS

Genotypic restrictions on plant regeneration from cultured cells have hindered the genetic transformation of most barley cultivars. Optimizi ng culturing protocols for specific cultivars of commercial interest m ay facilitate their genetic transformation. Plant regeneration from em bryogenic callus of 'Harrington', 'Morex', and 'Hector' as affected by certain protocol modifications was examined in replicated experiments . Regeneration was improved for all cultivars by separately autoclavin g certain components of the culture media and by reducing the amount o f embryogenic callus cultured per petri dish. Regeneration improvement s in response to various concentrations of copper and 2,4-dichlorophen oxyacetic acid were more genotype specific. This study suggests that t he development and use of genotype-specific protocols can enhance plan t regeneration. Enhancements in plant regeneration are expected to fac ilitate the transformation of commercial barley germplasm.