Bud Regeneration and Growth from Transgenic and Non-Transgenic Aspen (Populus tremula) Root Explants

Abstract

Poplars, including aspen, (Populus tremula), are fast growing trees employed in the wood industry and have a potential value for biomass and energy production. Vegetative propagation is carried out by cuttings, root suckers and grafting, but an increase of the propagation efficiency is highly desired. In vitro procedures are becoming available for efficient large-scale clonal propagation of poplar genotypes. These procedures can benefit from large-scale root culture in liquid media, based on the natural ability of aspen for shoot bud formation on roots (Carmi, 1994). The effect of different types of root expiants upon bud regeneration of aspen was studied using root segments from adventitious roots that formed on stem sections of two transgenic lines that harbored the rolB and rolC genes, and one non-transgeme line.