Micropropagation of Laburnum anagyroides Medic. through axillary shoot regeneration

An in vitro propagation system based on the proliferation of axillary buds has been developed for Laburnum anagyroides. Culture initiation was influenced by explanting season, with the maximum response obtained from explants harvested in spring and autumn while the lowest response was noted in summer explants. The best shoot induction was observed on Murashige and Skoog medium (MS) supplemented with 2.22 mu M6-benzylaminopurine (BAP). The basal media, type of cytokinin, and explant type were the most important factors affecting shoot multiplication of L. anagyroides. Medium comprised of 1/2MS salts was found to be more efficient for axillary shootmultiplication compared to full-strength MS or Wood Plant Medium (WPM) when using identical growth regulators. Shoot tip explants were more responsive than nodal segments of microshoots for micropropagation. In vitro-derived shoots, > 10 mm in length, were successfully rooted in medium containing 1/4MS salts and 2.68 mu M alpha-naphtalene acetic acid (NAA). In vitro-regenerated plantlets were adapted to ex vitro conditions and transferred to a greenhouse. This is the first report for successful in vitro propagation of L. anagyroides from bud explants of mature trees.