Activity of α-d-Galactosidase in Long-Stored Seeds of Vicia hirsuta

Abstract

Mature seeds of many crop species contain substantial amounts of soluble carbohydrates, including raffinose family oligosaccharides (RFOs) and cyclitol galactosides (Gal-C). These substances are hydrolysed by α-D-galactosidase (EC 3.2.1.22) during the early stages of germination, providing metabolic energy for the germination process. A decrease or inhibition of α-D-galactosidase activity can significantly reduce the germination rate. This study aimed to investigate changes in α-D-galactosidase activity during the long-term storage of Vicia hirsuta seeds and evaluate the association between the loss of enzyme activity and the decline in seed vigour and viability. V. hirsuta seeds were stored at 22 °C and 35% relative humidity for up to 25 years, and α-D-galactosidase activity and seed vigour changes were monitored at different time points. Storage of V. hirsuta seeds resulted in a loss of viability and vigour, accompanied by a decrease in α-D-galactosidase activity. The enzyme activity showed a significant correlation with seed germinability and vigour. Monitoring α-D-galactosidase activity in seeds subjected to long-term storage could be a simple and rapid method for determining the decline in vigour in seeds that utilize soluble galactosides as their storage materials.