Sucrose requirements and lipid utilization during germination of interior spruce (Picea glauca engelmannii) somatic embryos
1997
Carrier, D.J. | Cunningham, J.E. | Taylor, D.C. | Dunstan, D.I.
Both somatic and excised zygotic embryos of interior spruce (Picea glauca engelmanii complex) required exogenous sucrose in the medium for germination in vitro. Over a period of 29 days on sucrose-containing medium germinants with roots and epicotyls developed from both kinds of embryo, and their content of linolenic acid (9, 12, 15-18:3) increased about six- to eightfold. Without added sucrose, embryos showed retarded growth or were necrotic, and the content of linolenic acid was hardy detectable in their fatty acid profiles. Through 14C-sucrose uptake studies, it was determined that germinants consumed only 25% of the sucrose available in a 1% (wt/vol) sucrose-containing medium. Since no radiolabelled fatty acids were detected. it appears that externally supplied sucrose was not used in the synthesis of lipids. Although sucrose was present during plantlet development, 72% of the initial lipids were consumed. To some extent, the plantlets appeared to be obligate storage lipid utilizers.
显示更多 [+] 显示较少 [-]