Micropropagation of chinese redbud (Cercis yunnanensis) through axillary bud breaking and induction of adventitious shoots from leaf pieces

Factors affecting in vitro shoot production and regeneration of Cercis yunnanensis Hu et Cheng were investigated by comparing various growth regulators and explant types. For optimum shoot production from axillary buds, Murashige and Skoog (MS) media containing 6-benzyladenine, either alone or in combination with a low concentration of thidiazuron, resulted in the greatest number of shoots formed per explant (>3). Explants (2 mm long) containing one axillary bud placed in direct contact with the medium yielded the most shoots per bud (1.6) when grown on growth regulator-free medium. Root formation on 70-80% of shoot explants was accomplished using either indole-3-butyric acid or alpha-naphthaleneacetic acid in the medium, with significantly more roots formed on explants possessing an apical bud than those without the bud. Direct shoot organogenesis from leaf explants occurred on MS medium containing 10-30 muM thidiazuron, with up to 42% of leaf explants producing shoots.