Studies in Wild Oat Seed Dormancy

Abstract

A selected strain of wild oat (A. fatua L.) seed lost dormancy rapidly during moist soil incubation at 25.degree. C; seed kept similarly at 5.degree. C maintained a high level of dormancy. The activities of cytosolic dehydrogenase enzymes of the pentose phosphate pathway were assayed throughout a period of moist soil incubation at these 2 temperatures. A distinction was made between extractable dehydrogenases from the embryo and the endosperm regions of the caryopsis. Dehydrogenase activities monitored in seeds incubated at 25.degree. C gradually increased over the course of the investigation. The largest increases in activity occurred during incubation at 5.degree. C, the situation in which dormancy is maintained. No obvious connection could be found between dormancy breakage and increased activity of the pentose phosphate pathway dehydrogenases.