Asexual reproduction is reproduction by mitosis. It results in the creation of a new, individual genetically identical to the parent. It does not involve sex cells, which are produced through meiosis.
Plants reproduce asexually in many different ways. They may reproduce vegetatively—producing clones of themselves—or through the formation of spores. The vegetative organs of a plant are its roots, stems, and leaves. One example of vegetative reproduction involving a plant’s stem is seen in strawberries. Strawberry plants produce horizontal stems above the ground from which roots and new plants can grow. Such stems or runners are called stolons. Rhizomes are horizontal stems that run underground. Irises use rhizomes to propagate. Bulbs like garlic, tubers like potatoes, and corms like gladioli are also stems that are involved in vegetative reproduction.
Plants of the genus Bryophyllum reproduce through their leaves. Mitosis along the leaf margins produces tiny plantlets that fall off and become new plants. This is an example of reproduction by fragmentation. In fragmentation, a piece of the parent plant breaks off and develops into a new individual.
Some plants use their roots for asexual reproduction. Trees, such as poplars or aspens, and dandelions are common examples. Anyone who has ever tried to remove dandelions from a lawn knows first hand about their extensive root system!
Plants may also asexually reproduce by forming spores. A spore is a reproductive cell that produces a new organism without fertilization, that is, without the fusing of two sex cells. Spores are most conspicuous in flowerless plants such as liverworts, mosses, and ferns.
Seeds may be produced asexually as well as sexually. In apomixis, seeds are asexually produced from a diploid female sex cell. Apomixis is important in the propagation of hybrid plants. It preserves the vigor of the hybrid plants without the variability introduced by sexual reproduction.
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