First, self-propagation (direct drop and elastic propagation)
Self-propagation means spreading by plants themselves, independent of other media. The fruit or seed itself has weight, and when it matures, it will fall directly to the ground due to gravity, such as persimmons and olives. However, some capsules and pods will produce ejection force when the fruit is ripe and cracked, which will eject the seeds, such as five-core stone.
Second, the wind spreads.
Some seeds grow appendages shaped like flocs or feathers and fly in the wind. Most of the seeds with pinnate appendages are herbs, such as yellow quail in Compositae, and woody plants are willow and kapok.
Third, water transmission.
Water-borne seeds, whose surface wax is not in contact with water (such as water lilies), have air cells in their skins, whose specific gravity is lower than that of water, and can float on the water surface and spread through streams or ocean currents.
Four, animal transmission (ants, birds, mammals)
If you walk in the grass, the seeds or fruits of many plants will stick to clothes or trousers, or to other animals, or to animal foods such as Bidens bipinnata, Ficus, Plantago, etc. In addition, ants usually play the role of secondary disseminators in seed transmission. Fleshy fruits, such as berries, drupes and hidden flowers and fruits. Usually birds peck at fruits and spit out seeds to spread.
Extended data
Composition of plant seeds
Plant seeds are all developed from ovules. The fertilized egg in the ovule develops into endosperm, and the nucellus develops into seed coat, forming ceremony, and nucellus is generally absorbed and disappeared during seed formation. So the seed structure is often composed of embryo, embryo and seed coat? .
Embryo is the most important part of seed, which is mainly composed of germ (composed of growth point and young leaves), radicle (composed of growth point and root cap), hypocotyl (short axis connecting embryo and radicle, with cotyledons attached to it) and cotyledon seeds. After germination, radicle, embryo and hypocotyl form root, stem, leaf and transition zone respectively.