Effect of novel branching regulators on micropropagation of zantedeschia sprengeri (paco)

THE NOVEL branching regulators fluridone and imazalil (IMA) were examined for micropropagation of Paco (Zantedeschia sprengeri). IMA concentrations were 0, 4.5, 13.5 and 45µM in combination with 5µM benzylaminopurine (BAP). The shoots were transferred after 8 weeks to standard MS medium without IMA but with 5µM BAP. IMA resulted in a strong increase of new shoots from which the outgrowth was inhibited when IMA was present but that did grow out when IMA had been removed. Fluridone inhibits the biosynthesis of the endogenous regulator strigolactone. Increasing concentrations of fluridone were applied in combination with 13.5µM IMA for 8 weeks. Then the shoots were subcultured on standard medium without IMA and fluridone but with 5µM BAP for 8 weeks. Again a strong increase of new shoots occurred from which outgrowth was inhibited when IMA and fluridone were present but that did grow out when these regulators had been removed.