BIOL-1507EL Lecture Notes - Lecture 4: Germination, Radicle, Seed Dormancy
Document Summary
The growth of the embryo is usually arrested while the seed matures and is dispersed. Thus germination is not possible until the seed imbibes the water required for metabolic activity. During the early stages of germination, respiration may be entirely anaerobic, but as soon as the seed coat ruptured, the seed switches to aerobic respiration. Many seeds will germinate over a wide range of temperatures; they usually will not germinate either below or above a certain temperature. The minimum temperature for most species: 0 5oc. The optimum temperature: 25 30oc in some cases even if the external conditions are favourable for seed germination, some seed will fail to germinate, such seeds are said to be dormant. Collectively these changes are called after ripening. for example, those species that grow in temperate, the after ripening is triggered by low temperate of winter. Dormancy is of great survival value to the plants.