Plant regeneration from seedling explants of Juncus effusus

An in vitro plant regeneration method for Juncus effusus L. was established . Six to eight day old in vitro grown seedlings, cultured on Murashige and Skoog medium supplemented with benzyladenine (BA), 2-isopentenyladenine (2i P), or kinetin, showed multiple shoot regeneration within 4 weeks. Among th e three cytokinins, BA and 2iP induced the highest (88 and 86%, respectivel y) regeneration frequency, while no significant differences were noticed in regeneration frequency between control (without cytokinin) and kinetin. Th e in vitro generated shoots, upon subculture to the same shoot induction me dium, produced an average of 10 shoots on 2iP medium. The regenerated shoot s turned brown at the base, and gradually turned black, resulting in reduce d plantlet rooting. Addition of charcoal to the rooting medium resulted in increased rooting percentages, increased root and shoot growth and reduced browning, whereas addition of the antioxidants citrate and ascorbate did no t. Rooted plants, transferred to a commercial soil mix, had a survival rate of >95% in the greenhouse. All the plants that were transferred to wetland s survived. This was the first tissue culture study on this ecologically im portant wetland plant. (C) 2000 Elsevier Science B.V. All rights reserved.