Proliferation of Axillary Shoots of Chestnut in Temporary Immersion Systems

Shoots from European chestnut and hybrids of European and Asian chestnuts can be efficiently proliferated in liquid medium by temporary immersion (TIS) using RITA^® and Plantform™ bioreactors. The main challenges of applying TIS to these species were the lack of growth and hyperhydricity; problem solutions included the manipulation of the hormone concentration, the explant type, immersion frequency, and a support for maintaining shoots in a vertical position. After protocol optimization, explants cultured by TIS produced more rootable shoots than explants growing in semisolid medium, enabling increased number of rooted and acclimatable shoots. In this chapter, we will describe the protocols for proliferating chestnut by TIS in RITA^® and Plantform™ bioreactors, together with tips for avoiding the main pitfalls of the technique. The strategies applied to chestnut can be useful for culturing other woody plants in bioreactors.