Improved Plant Regeneration from Rosa xhybrida L. Leaf Explants

Abstract

Attempts to regenerate plants from leaf explants of Rosa xhybrida L. on Murashige and Skoog medium have met with limited success. We report improved regeneration of somatic embryos and adventitious shoots from leaves of `Golden Emblem' on N6 medium. Leaf explants were obtained from microshoots that had been in culture for 4 years. Leaves were placed on N6 medium containing various combinations of 0, 0.4, or 1.0 μM 2,4-D and kinetin for 20 days with an initial dark treatment of 12 days, then transferred to a medium without plant growth regulator. Adventitious shoots and somatic embryos were observed 3 weeks after transferring to medium without plant growth regulators. Leaf explants placed on media without 2,4-D failed to form embryos or shoots. The best combinations of 2,4-D and kinetin (0.4 and 0.4 μM, 0.4 and 1.0 μM, or 1.0 and 1.0 μM) induced regeneration percentages ranging from 21% to 39%. N6 appears to improve regeneration of somatic embryos and adventitious shoots from `Golden Emblem' leaf explants, but the interaction between media formulation and duration of exposure to 2,4-D and kinetin needs to be examined.