Difference Between Perisperm and Pericarp
The perisperm is the outer layer of mature seed. The pericarp or fruit is that which covers it. Most seed plants produce the pericarp as a fruit. That’s because the fruit’s function is to attract animals who eat it and disperse the seed.
The pericarp is usually more or less fleshy, though it may be dry like in nuts in some. It may or may not have seeds inside of it, as most fruits are either single-seeded (often with a stone) or contain two to many seeds that are released when taken apart from each other.
Perisperm is derived from especially in monocots. It is a type of endosperm storage that occurs near to the embryo in monocotyledons but not necessarily completely surrounding it. The term “perisperm” is derived from the Greek “peri,” meaning around, and Latin “sperm,” meaning seed.
Some plants have perisperms. The perisperm is very much like the fruit, but it does not contain seeds. It functions as a protective layer around the seeds and may contain other substances that aid in seed germination or establishment.
Examples of plants with perisperm are “Myrica Rubra” (red bayberry), “Crataegus” (hawthorn), “Tilia tomentosa” (also known as Basswood), and “Lycopersicon esculentum” (tomato).
Plants produce the perisperm as fruits to attract animals that eat them and disperse the seeds that may have been dispersed from earlier stages of development or from other plants. Many approaches exist to determine the role of the perisperm in plant reproduction and dispersal.
Besides, whether or not there is a specific beginning point in an angiosperm flower where an embryo first develops to produce a perisperm is controversial, with most evidence pointing to it being present in all flowers.
The perisperm allows the seeds to be dispersed. In some cases, this is done by animals eating the fruits and excreting the seeds away from the parent plant. The fruit may also contain substances that attract animals, such as nectar or sugar.
The fruit in “Crataegus” (hawthorn) contains a sweet, juicy pulp and small pits with small seeds inside of them. Hawthorn produces these fruits for many reasons. They are eaten by birds, which then disperse the seeds out of their bodies.
Birds also eat these fruits, and the seeds pass through their digestive systems. They are excellent for attracting birds because of the seeds’ small size and the pits they contain. The birds don’t realize that they have eaten the seeds, so they are passed through their bodies and into other areas near the parent plant.
These areas tend to be mixed plant communities (some plant species typically do not like to be in floral communities), providing food sources for many species, including those that feed on these fruits. Seed germination occurs when the seed is located in the pit. Seedlings of “Crataegus” will begin growing roots and leaves from these seeds.
The perisperm is a part of the seed that surrounds it but does not come completely into contact with it. This is different from the seed coat, or sarcotesta, which completely envelops the seed. “Crataegus” produces seeds in pits (a type of fruit) and also produces a perisperm. All of its seeds are enveloped by the fruit and the perisperm as well.
The perisperm can be a number of different tissues, depending on the plant species it is in. In some species, it can be fleshy or fatty tissue surrounding an embryo that has been suspended in honeydew. In some plant species, the perisperm has multiple layers and forms an outer layer separate from the seed.
In “Crataegus,” it is a fleshy and pulpy tissue that surrounds the whole pit, as well as the seeds inside of it.