Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, Beijing Forestry University,Beijing 100083, P. R. China
Abstract:
Suspension cultures initiated from callus derived from petiole explants of aspen hybrid (Populus tremuloides × P. tremula) produced somatic embryos. Callus was induced on a MS medium supplemented with 5 mg·L−1 2,4-D and 0.05 mg·L−1 zeatin under light conditions. Embryogenic calli were obtained when a subsequent subculture of calli was suspended in the
same basal medium with 10 mg·L−1 2,4-D. The highest number of globular embryos were induced from embryogenic calli by cell suspension culture in a MS liquid
medium supplemented with 10 mg·L−1 2,4-D. Genotype and 2,4-D concentration were vital to the induction of embryogenic calli producing competent cells. Embryogenic
calli for each genotype were heterogeneous. Green calli with gel-like consistency could yield more competent cells than light
yellow embryogenic calli. However, some globular embryos broke into slices and some developed abnormally after one month of
culture under the same or other hormonal conditions.
Supported by the National “863” Project (Grant No. 2002AA241071) and the National “948” Project (Grant No. 19980404)]