Plumule vs. Radicle

Main Difference

The main difference between Plumule and Radical is that Plumule is the embryonic stem that forms the part of the seed embryo, whereas Radicle is the embryonic root that forms the part of the seed embryo.

Difference Between Plumule and Radicle

Comparison Chart

Plumule vs. Radicle

The growth of the plumule occurs after the growth of radicle and form the stem n seedling development of radicle, whereas the growth of radicle from the seed occurs first by the micropyle in the seed during germination and it forms the roots of the new seedling. The process of photosynthesis of plumule is responsible for the production of food for the growth of the underdeveloped plant; however, the absorption of water from the soil is done by radicle that is necessary for the new plant development. The growth of the plumule is upwards and upright out of the soil, but the growth of the radicle is downwards and below under the soil.

The color of the plumule is slightly whitish, less than the radicle, while the color of the radicle is more whitish. The development of plumule leads to the formation of the plant’s future stem, shoot, and leaves; however, the development of radicle is responsible for the formation of future roots of a new plant; radicle appears from the seed by the micropyle, and during germination of the seed, it is present at the top of cotyledons.

Plumule has a positively phototrophic property to respond to the stimulus of light to grow; however, in the case of the radicle, and it has a negatively phototrophic property because it doesn’t respond to the stimulus of sunlight.

Plumule has a negative property towards hydrotropism, as its growth does not depend on the water concentration and its growth is opposite to the direction of water, whereas radicle has a positively hydrotropic property as its growth depends on the stimulus by water gradient for the absorption of water for metabolic processes, and always grows in the direction of moist soil to prevent water scarcity; the root starts to bend and grow in the direction of water as soon as it senses the existence of water.

Plumule has a negative property towards geotropism; therefore, it is negatively geotropic as they bend to grow away from the soil and toward the higher level while radicle has a positively geotropic property because their growth is towards the center of the earth, down into the soil.

What is Plumule?

It is the elementary part of the seed embryo that develops in to shoot or stem and further into true leaves of a new plant, but in case of some seeds, for example, the sunflower plant consists of plumule that has a small cone-shaped structure with the absence of any leaf structure. The location of the plumule is between the two cotyledons of seed. During the germination of the seed, it is present at the top of the cotyledons. The growing pointed end of the epicotyl is plumule, and the future stems, flowers, and leaves of the plant develop from a small sprout that is epicotyl.

The plumule is responsible for the production of food by the process of photosynthesis, which, in turn, is important for the growth and development of a plant. Plumule has a positively phototrophic property, as it responds to the stimulus of light and grows in the direction of the sunlight. The growth of the plumule also depends on the growth of cotyledons; the growth of plumule does not take place until the cotyledons are grown above the soil.

It refers to epigeal germination, which is the development of the plumule later to the growth of cotyledons at the top of the ground. Although leafy structure on the plumule of the broad bean seed; these seeds are formed when the plumule grows upward out of the soil along with the cotyledons that stay under the surface, it refers to hypogeal germination which is the occurrence of the plumule upward the soil; on the other hand, the cotyledons stay under the surface of the soil.

Plumule varies in shape and size according to the species, but most of the plumules are cone-shaped and less whitish colored. The growth of the plumule becomes smaller if an adequate amount of food is stored inside the cotyledons and angiosperms itself, but the growth of the plumule becomes larger when the minimum amount of food is stored in the seed. It grows large enough with proper true leaves that are suitable for the process of photosynthesis for the synthesis of food.

Environmental factors are also responsible for managing particular characteristics of the development of a seedling. The plumule has a negative property towards geotropic as it grows away from the ground. It strongly responds to the stimulus of sunlight as it is positively phototropic and negatively hypertrophic.

What is Radicle?

During germination, the first part that originates from the seed is radicle, which is the radicle is the embryonic root of a new plant and further develops and becomes the true root of the plant. It is originated from the seed by the micropyle. The classification of radicle in seedlings can be classified in two types according to the direction of growth; antitropous are those outgrowths of radicles that grow away from the hilum or the seed coat whereas syntropous are those radicles that grow in the direction of the hilum or core of the seed that is the origin of attachment with its seed vessel.

The reason behind the decaying of the radicle is the damping-off of a seed before emerging of the seedling. It is a disease or condition that deliberate or kills seed or embryonic root by several infections and pathogens. It is mostly encouraged by wet, damp, and cool conditions that can even cause visible dark spots on the radicle and, at last, cause the death of the seedling. During the sprouting or germination stage, radicle that sprouts from the seed are the first growth of a basic plant. The main function of radicle being into the soil is the absorption of water for the further development of a new plant.

The calyptra is the root cap tissue that is present at the tip of root protects the radicle whose main function is the absorption and transportation of water and nutrients for the process of photosynthesis of leaves. Radicle is the first true root of a seedling that appears as a white-colored short structure out of the seed.

Environmental factors are also responsible for managing particular characteristics of the development of a seedling as well as during the development of implant establish the orientation of the seedling. The radicle has a positively geotropic property because it grows in a downward direction under the ground. It has a negatively phototrophic property because it doesn’t respond to the stimulus of sunlight and has a positively hydrotropic property as its growth depends on the stimulus by water gradient for the absorption of water for metabolic processes and always grows in the direction of moist soil.

Conclusion

An embryonic plant has both parts plumule and radicle; however, they can be differentiated by their future development of parts of the plant. Plumule is the embryonic shoot that develops into future leaves, stem, and their function is to produce food by photosynthesis, whereas radicle is the embryonic root that develops into the future root, and its function is the absorption and transportation of water and nutrients from the soil.