Establishing an in vitro regeneration system from hypocotyls of Chrysanthemum lavandulifolium.

An efficient regeneration protocol had been established for plantlet regeneration from hypocotylinduced calli of Chrysanthemum lavandulifolium, which laid the foundation for genetic transformation of C. lavandulifolium. When long hypocotyls from the seeds that germinated in the dark for 7 days were cultured on the Murashige and Skoogs (MS) medium containing 1.0 mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) and 0.5 mg/L 6-benzyl aminopurine(6-BA) for 15 days, the calli inducing rate could reach the maximum of 86.66%. The calli were light yellow with almost uniform size. Following approximately 30 days of culture on the MS medium, adventitious buds were differentiated. The highest adventitious bud rate (25.50%) with an average of about 4.25 adventitious buds per explant was obtained from calli cultured on a MS medium without 6-BA. The rooting rate was 100% when the adventitious buds were cultured on the 1/2 MS medium supplemented with 0.1 mg/L naphthaleneacetic acid (NAA) for 15 days. After acclimatized to greenhouse conditions, normal growth and blossom C. lavandulifolium plants were obtained.