Evaluation of a New Temporary Immersion Bioreactor System for Micropropagation of Cultivars of Eucalyptus, Birch and Fir

Abstract

The use of liquid instead of solid culture medium for the micropropagation of plants offers advantages such as better access to medium components and scalability through possible automation of the processes. The objective of this work was to compare a new temporary immersion bioreactor (TIB) to solid medium culture for the micropropagation of a selection of tree species micropropagated for commercial use: Nordmann fir (Abies nordmanniana (Steven) Spach), Eucalyptus (E. grandis x E. urophylla), Downy birch (Betula pubescens Ehrh), and Curly birch (Betula pendula var. carelica). Cultivation of explants in the TIB resulted in a significant increase of multiplication rate and fresh weight of Eucalyptus and B. pendula, but not Betula pubescens. In addition, the fresh weight of embryogenic tissue and the maturation frequency of somatic embryos increased significantly when an embryogenic cell line of A. nordmanniana was cultivated in the TIB compared to solid culture medium. These results demonstrate the potential for scaling up and automating micropropagation by shoot multiplication and somatic embryogenesis in commercial tree species using a temporary immersion bioreactor.