Sucrose and raffinose contents and acquisition of desiccation tolerance in immature maize embryos

We report preliminary experiments to test the hypothesis that two sugars are involved in the acquisition of desiccation tolerance in immature maize embryos. Sucrose and raffinose were quantified during embryo development, at 16-27 days after pollination (DAP) and during slow dehydration. Embryos were exposed to slow drying either upon excision (18 and 16 DAP) or after an incubation treatment resulting in a decrease in sucrose (18 DAP). The sugars were separated by HPLC with a refractive-index detector; composition was determined by comparing peak areas of interest with those of individual sugar standards. Although further evidence is needed, our results do not appear to support the hypothesis.