1. As maturation advances, the external conditions for the germination of Sonchus oleraceus seeds at room temperature change very remarkably. In very young stages, the seeds with the coats intact (or cypsela) can germinate on moist fluting paper, but they are unable to germinate at all under shallow water. The cypsela in full maturation, on the contrary, no longer germinate on the moist paper, though they are now able to germinate under the water. 2. The germination power of mature seeds varies according to the temperatures of their maturation season, and it is affected by the duration of storage, as well as the presoaking treatment immediately before the test. 3. To germinate the mature seeds with the coats intact, moist paper bed is prefered to shallow water bed when the temperature is low, but that situation reverses entirely at high temperature. 4. In the germination mechanisms of the seeds of Sonchus oleraceus, the seed coat seems to take peculiar part, giving mechanical resistance of certain degrees to the swelling embryo and restricting its water intake partially.
Mendeley出力
