In vitro propagation of Quercus robur by Plantform bioreactor

2.1 = IN VITRO PROPAGATION OF QUERCUS ROBUR L. BY PLANTFORM BIOREACTOR ENRICO GATTI1, AYLIN OZUDOGRU2, MAURIZIO LAMBARDI2, ELISABETTA SGARBI1 1) Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola, 2, Padiglione Besta, 42122 Reggio Emilia, Italy 2) IVALSA/Trees and Timber Institute, National Research Council (CNR), via Madonna del Piano 10, 50019 Sesto Fiorentino (Firenze), Italy Plantform bioreactor is a new system recently developed to improve in vitro plant cultures. This bioreactor is based on a temporary immersion system (TIS) with a ventilation that ensures the regular air renewal inside the plastic box. This technique has been tested for the large scale micropropagation of ornamental and crop plants and demonstrated to be able to improve some growth parameters (1, 2). Pedunculate oak (Quercus robur L.) proved to be a recalcitrant species to micropropagation (3). Indeed, although a protocol for in vitro propagation of this species has been previously reported (4), the proliferation rate of shoots still remains unsatisfactory. Hence, the Plantform bioreactor was tested in this study, with the aim to evaluate its efficiency in promoting shoot proliferation of oak. The results were compared with those obtained with cultures on gelled medium. Nodal segments ( 10-15 mm, on average) of Q. robur were taken from previously established in vitro shoot cultures and placed horizontally both in Microbox vessels, on Woody Plant Medium added with sucrose (20 g/l), agar (6 g/l) and 6-benzylaminopurine (0.2 mg/l), and in Plantform with the same medium without agar. Two different conditions of temporary immersion were tested in Plantform: 12 min/8 h and 8 min/16 h. Air was renewed for 15 min/4 h. Significant differences in terms of RGR (Relative Growth Rate) of shoots, based on fresh weight, were observed when the two techniques (Microbox and Plantform) were compared after 10 weeks of culture. The highest value of RGR was obtained with the Plantform bioreactor, without differences between the two conditions of temporary immersion (Fig.1, 2). Plantform seems to be an effective, alternative method to promote a rapid and vigorous growth in Q. robur shoot cultures. Rooting ability, acclimatization and some morpho-physiologial parameters of the leaflets will be considered afterwards, in order to evaluate the quality and the health of the micropropagated plantlets. 1) Welander M., Kuznetsova T., Persson J. and Sayegh A. (2013). Evaluation of a new vessel system for micropropagation based on temporary immersion system (TIS) and applied physiology. Proceedings of 8th IVCHB, Coimbra, June 2-7. p.36 2) Lambardi M. (2012). Micropropagazione in coltura liquida con sistema ad immersione temporanea. Riv. Frutticolt. Ortofloricolt. 12: 32-38. 3) Vieitez, A.M., San-Jose M.C. and Vieitez, E. (1985). In vitro Plantlet Regeneration from Juvenile and Mature Quercus robur L. J. Hortic. Sci. Biotech. 60: 99-106. 4) Gatti E. and Sgarbi E. (2014). Micropropagation of Quercus robur: Explant Sources and Cultural Conditions Differently Affect In Vitro Responses, Acta Hort., in press.