In vitro tillering—An effective way to multiply high-biomass plant Arundo donax

• An effective alternative for large-scale multiplication of giant reed plants.
• About 700 plants ready for planting produced from one axillary bud in one year.
• Micropropagation of giant reed is strongly affected by the type of gelling agent.
• TDZ improves shoot multiplication but negatively affects root morphology.

In vitro shoot multiplication of giant reed as an alternative to propagation by stem or rhizome segments was optimized. The culture was initiated from stem segments containing an axillary bud. Shoot multiplication was improved by adjusting media composition in terms of cytokinins, auxin and sucrose content and the type of gelling agent. The most effective shoot multiplication was on medium solidified with Gelrite and supplemented with BAP or TDZ. However, TDZ had the negative impact on root formation and root morphology. Individual rooting stage was not a prerequisite before transplantation to the soil because well-developed roots were formed on shoots in the multiplication medium with BAP, although the addition of NAA enhanced root formation. Using the suggested approach, about 700 rooted and acclimatized plants can be produced in one year starting from one axillary bud.