Types of germination
- Epigeal germination (epi-upon and ge-earth):
- Seed germination in which the seed leaves (cotyledons) emerge from the ground and function as true leaves is called epigeal germination.
- During root establishment, the hypocotyl begins to elongate by quick cell division and push the seed cotyledon up which breaks the soil crust and projects into the air through the soil.
- Afterwards the cotyledon open, plumule growth continues and the exhausted cotyledon wither and falls to ground.
- It is found in bean, soybean, black gram, green gram, groundnut, pigeon pea, sunflower, pine seeds etc.
- Hypogeal germination:
- It is the kind of seed germination in which the seed leaves (cotyledons) remain below the ground.
- The cells of epicotyls divide faster and increase the length of epicotyls, which pushes the seed leaves below the ground.
- Regardless of above and belowground, the cotyledons continue to provide nutrition to the growing points throughout germination.
- Most cereals or monocots except onion are hypogeal type of germination. Some winter pulses like pea, gram, lentil etc also have hypogeal type of germination.
