Dependence of germination of wheat grains after the treatment by impulse pressure and long-term storage on the vitreousness of endosperm

Abstract

The aim was identification of patterns of changes in the physical and chemical state of biopolymers in durum and soft wheat seeds after the treatment of impulse pressure (IP) and during the storage of seeds. It was found that durum wheat seeds accumulated microcracks over the structure of the glassy endosperm after the IP treatment, while soft wheat seeds reacted to IP treatment by “collapsing” air gaps in the loose endosperm, as well as by vitrification of amorphous areas that were in a highly elastic state and the transition of crystalline areas to vitreous ones. The vitreous content of durum seeds decreased, while that of soft seeds increased linearly after the treatment by IP and storage. Treatment of soft wheat seeds with IP and storage increased their germination, growth and quality of seedlings due to vitrification of the seed endosperm. The decrease in the vitreousness of durum wheat grain after the treatment with IP and storage led to deterioration in the quality of grain and sprouts during storage. So the glassy state in seeds is suggested to serve as a stabilizer. The rapid progress of deterioration may represent a weakening of the glassy state.