Abstract:

In the present study, one clone of transgenic hybrid aspen（Populus tremula ×P. tremuloides）from tissue culture was used as the materials and non-transgenic clone as the control. The contents of endogenous plant hormones, including IAA, ABA and GA, were measured by ELISA in different genotypes and different rooting types. The purpose was to study effects of changes in endogenous plant hormones, and their interaction on rooting of hybrid aspen during tissue culture. The results showed that there was extremely significant variation in IAA and ABA contents among different rooting types of the ramets, regardless transgenic or non-transgenic plants. GA content from different rooting ramets was all highest with about 400-500 ng·g^-1. In transgenic ramets, ABA and IAA concentrations were relatively low in about 150 and 200 ng·g^-1, respectively, at which they were good for promoting the rooting of the plants. Non-transgenic plants in different rooting types all could get the roots, but the phytohormone contents in direct rooting ramets were generally higher than those of the callus rooting ramets. The low IAA/ABA and high GA/ABA and GA/IAA played an important role in the plant rooting.

Key words: hybrid aspen (Populus tremula×, P. tremuloides), transgenic, plant endogenous hormones, rooting