Seed Dispersal

Key Notes :

Definition of Seed Dispersal:

  • Seed dispersal is the process by which seeds are spread away from the parent plant to reduce competition and ensure species survival.

Importance of Seed Dispersal:

  • Reduces overcrowding among plants.
  • Prevents competition for sunlight, water, and nutrients.
  • Helps plants colonize new areas.
  • Increases the chances of survival for seeds.

Methods of Seed Dispersal: Seeds can be dispersed by:

  • Wind:
    • Light and small seeds with wings or hairs (e.g., dandelion, maple).
  • Water:
    • Seeds that float or have waterproof coverings (e.g., coconut, lotus).
  • Animals:
    • Seeds with hooks or sticky surfaces cling to animals (e.g., burdock).
    • Edible seeds are dispersed after being eaten by animals (e.g., berries, guava).
  • Explosion:
    • Some plants have pods that burst open, scattering seeds (e.g., pea, balsam).
  • Gravity:
    • Heavy seeds fall directly beneath the parent plant and may roll away (e.g., apple, mango).

Adaptations for Dispersal:

  • Wind-dispersed seeds: Lightweight, wing-like structures, or silky hairs.
  • Water-dispersed seeds: Buoyant and water-resistant.
  • Animal-dispersed seeds: Colorful, tasty, or sticky to attract animals.
  • Explosive seeds: Tightly packed pods with tension for bursting.

Benefits of Seed Dispersal:

  • Promotes biodiversity by spreading plants across different regions.
  • Prevents diseases and pests from affecting all seeds of the same plant.
  • Allows plants to adapt to various environmental conditions.

Examples:

  • Wind: Cotton, sycamore.
  • Water: Water lily, coconut.
  • Animals: Mango, tomato.
  • Explosion: Poppy, touch-me-not.

Let’s practice!