There are two primary patterns of germination – epigeal and hypogeal.
Epigeal germination is when the plumule and cotyledons or seed leaves emerge above the surface of the soil. This is the most common form of germination, and is used by plants like beans and peas. During this type of germination, the seed coat essentially splits as the cotyledons push through the soil.
The plant then grows directly upwards and the true leaves continue to emerge.
Hypogeal germination is much less common. This occurs when the cotyledons remain inside the soil and stored food is used to fuel growth of a small “stem” from the seed. The plumule emerges above the ground along with leaves that are distinct from the cotyledons – typically shaped differently and a different color.
This type of germination is seen in melons and squash, where the cotyledons are transformed below the soil into the root and stem of the young plant.
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What are the 2 types of seed germination name them and give one difference between them?
The two main types of seed germination are epigeal and hypogeal. The primary difference between these types is in the amount and type of growth that take place after germination.
Epigeal germination occurs when the radicle of the seedling emerges from the soil and the seedling grows above the soil surface. During this process, the embryonic leaves of the seedling expand within the cotyledons, forming a “two-leaved” stage in which two leaves are visible.
In epigeal germination, the cotyledons remain attached to the seedling and form part of the first pair of true leaves.
Hypogeal germination takes place when the cotyledons of the seedling remain within the ground. The radicle of the seedling emerges from the soil during hypogeal germination, but the seedling typically does not emerge above the soil surface.
During this process, the embryonic leaves expand relatively slowly and the cotyledons stay attached to the seedling. By the time the first pair of true leaves appear, the cotyledons have usually been shed and have begun to decay or become nutrient sources for the seedling.
What are the two difference between epigeal and hypogeal germination?
The two main differences between epigeal and hypogeal germination are the positioning of the seedling and the rate of development. With epigeal germination, the cotyledon tissue of the seedling emerge from the soil and pushes the seed coat aboveground.
During hypogeal germination, the cotyledon tissue stay within the soil, and only the stem and leaves of the seedling emerge aboveground.
When it comes to rate of development, epigeal germination is typically slower compared to its hypogeal counterpart. With epigeal germination, the seedlings take longer to fully emerge aboveground as the cotyledon have a limited ability to actually push their way through the soil.
Conversely, with hypogeal germination, the seedling can develop quicker as the cotyledon are already in the surrounding soil and can easily absorb the nutrients and water in the area for early growth.
What type of process is germination?
Germination is the process of a seed developing and unfurling after dormant or suspended animation. This process involves the seed absorbing water, releasing oxygen and utilizing energy stored in the seed in order to grow and eventually sprout into a seedling.
This process is usually triggered by changes in temperature, pH and moisture, though some seeds may require more specific conditions in order to sprout. The end result of the germination process is a new plant that can continue to grow and eventually become fully grown.
What is epigeal vs Hypogeal emergence?
Epigeal emergence is the type of emergence when a seedling’s seed leaves, the cotyledons, or leaves that contain nutrients, rise above the soil and up into the air. This type of emergence is seen in broad-leaved and inflorescence plants, such as tomatoes and cereals.
This emergence helps to promote photosynthesis as the plant grows, as it allows sunshine to hit the leaves and initiate the process. Additionally, the emergence of the seed leaves also allows for proper transpiration and respiration for the plant.
Hypogeal emergence, on the other hand, is the type of emergence seen in some flower and vine seedlings where the cotyledons stay below the surface of the soil, with the true leaves pushing up from the ground.
This type of emergence is found in plants such as beans and peanuts, and is beneficial to their growth in comparison to epigeal emergence. The primary benefit of hypogeal emergence is that the seed sets provide nourishment throughout the development of the plant and allow the plant to begin photosynthesis as soon as it sprouts.
Additionally, hypogeal emergence provides minimal exposure of the cotyledons to damages caused by the environment, a factor that can prove beneficial to the plant in terms of growth and development.
What is epigeal germination and types?
Epigeal germination is a type of seed germination when a plant embryo breaks through the seed coat and emerges above the soil line. It is also known as hypogeal germination. The embryonic root and shoot emerge from the seed and grow above the soil surface in this type of germination.
The seed coat splits as the shoot and root extend themselves, forming the seedling.
There are two main types of epigeal germination. Monocotyledons, such as corn and grasses, generally exhibit mesocotyl emergence; the stem of the seedling emerges from the seed medullary canal prior to the emergence of the shoot.
In dicotyledonous plants (such as legumes and other broadleaf species) the seedling exhibits epicotyl emergence; the seedling emerges from the seed coat first, followed by the root. These two germination categories are distinguished by the position of the embryonic root and shoot: in mesocotyl emergence, the shoot system is positioned above the root system within the seed, while in epicotyl emergence the root system is above the shoot system within the seed.
What 4 factors have to be for seeds to germinate?
For seeds to successfully germinate, four key factors are required: water, correct temperature, oxygen, and light.
Water is vital for a seed to be able to break dormancy, expand, and then germinate. If the seed remains too dry, the seed coat can become impermeable and the seed will not be able to germinate. Water also helps activate essential enzymes that are necessary for germination.
Different types of plants have different temperature requirements for germination. Generally, higher temperatures will speed up the process but extreme temperatures can be detrimental and lead to unsuccessful germination.
Oxygen is needed by the seedling’s emerging root. This gas is necessary for the metabolic activities of the seedling. A lack of oxygen can stop the seed from germinating.
Light is another requirement for certain seeds to germinate. Light acts as a cue for the seed to start the germination process. With some plants, germination can either be inhibited or stimulated depending on the amount and quality of light being exposed.
What 3 things are needed for germination?
In order for any process to be successful,there are three key components that are essential for germination: moisture, oxygen, and heat.
Moisture is absolutely necessary for germination of seeds. The seed coat needs to be able to absorb water and swell before the embryo can break out of the seed and start to grow. Without this step, the process will not continue.
As water is absorbed, the seed coat will rupture, creating the need for oxygen. Oxygen is necessary to facilitate the metabolic processes in the embryo, such as respiration and germination. Without oxygen, the embryo cannot survive.
Heat is also necessary for germination, but the type and amount required will vary depending on the seed. Some seeds require exposure to temperatures below freezing in order to germinate, which is more commonly seen in dormant seeds.
For other seeds, higher temperatures are needed in order to initiate germination.
