An integrated physiological and proteomic approach was used to investigate the effects of high gellan gum concentration in the medium during maturation of somatic embryos of hybrid larch, by comparing embryos incubated in media with a high gellan gum concentration (8 gL-1) and the conventional concentration (4 gL-1) after 1, 3, 6 and 8 weeks of maturation. Due to the reduced availability of water in the 8 gL-1 medium, the embryos cultivated on it had lower osmotic potential and water contents, but higher dry weights, at 8 weeks than embryos cultivated on the standard medium. The high gellan gum concentration induced a desiccation as occurring during zygotic embryo maturation. Total soluble proteins were extracted from embryos with TCA-acetone after 1 and 8 weeks of maturation on media with 4 and 8 gL-1 of gellan gum, and separated by two-dimensional gel electrophoresis at pH 4-7. More than 1100 proteins were reproducibly detected on each gel. At 1 and 8 weeks respectively, the abundances of 62 and 49 spots detected in analyses of embryos matured at the two gellan gum concentrations significantly differed. Among 62 significantly differing spots at 1 week of maturation, the corresponding proteins of 56 were reliably identified by LC-MS/MS, and were found to be mainly involved in “Carbohydrate metabolism”, “Genetic information processing” or "Environmental information processing” according to KEGG taxonomy. Both physiological parameters and the proteins identified suggested that the embryos were stressed when they were cultivated on 4 gL-1of gellan gum.