Submitted to: Plant Cell Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 20, 1998
Publication Date: N/A
Interpretive Summary: This study was conducted to improve the potential for the genetic engineering of barley. Genetic engineering techniques hold great promise for increasing the yield, quality, and usefulness of agricultural commodities such as barley. Examples of potential uses of genetically engineered barley include the introduction of genes for improved malting quality, improved insect and disease resistance, and increased nutritional value. Such improvements are expected to increase the profitability of barley growers and processors, decrease the cost to consumers, and improve the environment by reducing dependence on synthetic chemicals. A basic requirement of genetic engineering techniques is that the tissues into which genes are introduced are capable of producing green, fertile plants. Cultured barley tissues, especially those of important cultivars, do not efficiently meet this requirement. Problems such as low numbers of regenerated plants, the regeneration of albino plants, or mutant plants are common. Certain changes to technique can be made, however, which may decrease these problems. The current study found that changing the nutrition and hormones given the barley tissue culture, reducing the toxicity of the culture medium, and growing the cultures in an uncrowded manner increased the numbers of green, normal plants that could be regenerated. By combining all these elements into one system, the efficiency of regeneration was increased by 10 times.
Technical Abstract: Genotypic restrictions on plant regeneration from cultured cells have hindered the genetic transformation of most barley cultivars. Optimization of culturing protocols for specific cultivars of commercial interest may facilitate their genetic transformation. Replicated experiments examined plant regeneration from callus tissues of 'Harrington', 'Morex', and 'Hector' in response to certain modifications of protocol. Regeneration was improved for all cultivars by separately autoclaving certain components of the culture media, and by reducing the amount of callus cultured per petri dish. Regeneration improvements in response to various concentrations of copper and 2,4-dichlorophenoxyacetic acid were more genotype-specific. This study suggests that the development and use of genotype-specific protocols can enhance plant regeneration and may facilitate the transformation of commercial barley germplasm.