What are the phases of germination?
The phases of germination are as follows:
1. Imbibition: The process begins when a seed absorbs water, causing it to swell and rehydrate. This phase helps activate enzymes needed for germination.
2. Activation: As imbibition occurs, certain enzymes become activated, initiating metabolic activities within the seed. These enzymes break down stored food reserves to provide energy for growth.
3. Respiration: Once activated, the embryo resumes respiration, breaking down stored nutrients to release energy for metabolic processes. Oxygen is required, and carbon dioxide and water are produced as byproducts.
4. Emergence of the radicle: The radicle, which develops into the primary root, emerges from the seed. It starts growing downward into the soil, providing anchorage and nutrients to the developing plant.
5. Growth of the shoot: Once the radicle has established itself, the shoot or plumule emerges from the seed and grows upward towards the light. The shoot contains the embryonic leaves (cotyledons) and meristematic tissue, which gives rise to the future stem and leaves.
6. Development of true leaves: After the shoot emerges from the soil, it starts producing true leaves, which are distinct from the cotyledons. True leaves take over the role of photosynthesis from the cotyledons.
7. Establishment: The plant continues to grow and develop, establishing a root system and producing more leaves. This phase marks the transition from the seedling stage to a mature plant.
It is important to note that these phases may vary depending on the species of plant and environmental conditions.