EVALUATION OF 10 CANADIAN BARLEY (HORDEUM-VULGARE L) CULTIVARS FOR TISSUE-CULTURE RESPONSE

Ten Canadian barley cultivars - Abee, Deuce, Ellice, Harrington, Manley, Bonanza, Conquest, Duke, Heartland, and Samson - were evaluated for tissue-culture response. Callus was obtained from embryos 3-5 d post anthesis from all cultivars. Fertile plants were regenerated from eight. Abee cultures gave the best response in terms of the number of plants regenerated, while Bonanza and Samson cultures produced no regenerated plants. Heartland and Deuce were selected for further study to determine optimum growth-regulator concentrations for callus production and plant regeneration. Two growth regulators - 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) - were evaluated at five concentrations (0. 5, 1.0, 2.5, 5.0 and 10 mg L-1). Maximum regeneration rates were achieved with Gamborg's B5 medium supplemented with 2.5 mg L-1 2,4-D. Thirty-four Heartland and 19 Deuce regenerants were produced per 100 embryos cultured.