The effect of carbohydrate source on the development of Brassica napus L. immature embryos in vitro

The effect of fructose, glucose, maltose and sucrose at various concentrations on Brassica napus embryos was studied. The morphogenetic reaction depended on the type and concentration of sugar in the medium. The frequency of developing embryos was highest on sucrose, followed by maltose and glucose. Fructose did not stimulate embryo growth. Spectrophotometry of autoclaved fructose showed an absorbance rise between 260-320 nm that could correspond to the formation of furfural derivatives. Autoclaving-induced toxicity probably inhibited embryo growth heart-shaped stage embryos developed on filter-sterilized fructose. The frequency of developing embryos increased with sugar concentration, but normal embryogenesis occurred only on 1% sucrose and maltose; at higher concentrations callus and/or shoots were formed. On media with 6% sucrose and 12% maltose, shoots and somatic embryos were produced.