Corm

views updated May 17 2018

Corm

A corm is a modified, upright, swollen, underground stem base of an herbaceous plant. Corms serve as a perennating organ (allowing the plant to live from season to season), storing energy and producing new shoots and flowering stems from one or more buds located in the axils of the scalelike leaves of the previous year. Corms differ from superficially similar bulbs in that their leaves are thin rather than fleshy, and they are entirely composed of stem tissues.

Herbaceous plants are perennials, meaning that they have a lifespan of several to many years. However, after each growing season the aboveground parts of herbaceous plants die back to the ground, and new growth must issue from below ground to begin the following season. In the case of cultivated species such as gladiolus (Gladiolus communis ), crocus (Crocus sativus ), and water chestnut (Eleocharis tuberosa ), the new herbaceous growth develops from underground corms. In fact, the corm of the water chestnut is eaten.

Horticulturalists usually propagate these species using corms, which develop small cormels from lateral buds on the sides of the parent corm. A relatively vigorous production of cormels can be stimulated by wounding the parent corm, for example, by making some sharp, but shallow, cuts on its base. To cultivate these plants, the cormels are split off and individually planted, rightside up, and a new plant will develop. The use of corms to propagate new plants in these ways does not involve any exchange of genetic information, and is referred to as vegetative propagation because the parent and progeny are genetically identical.

Corm

views updated May 18 2018

Corm

A corm is a modified, upright, swollen, underground stem base of a herbaceous plant . Corms serve as a perennating organ , storing energy and producing new shoots and flowering stems from one or more buds located in the axils of the scale–like leaves of the previous year. Corms differ from superficially similar bulbs in that their leaves are thin rather than fleshy, and they are entirely composed of stem tissues.

Herbaceous plants are perennials, meaning that they have a lifespan of several to many years. However, after each growing season the above-ground parts of herbaceous plants die back to the ground, and new growth must issue from below ground to begin the following season. In the case of cultivated species such as gladiolus (Gladiolus communis), crocus (Crocus sativus), and water chestnut (Eleocharis tuberosa), the new herbaceous growth develops from underground corms. In fact, the corm of the water chestnut is eaten.

Horticulturalists usually propagate these species using corms, which develop small "cormels" from lateral buds on the sides of the parent corm. A relatively vigorous production of cormels can be stimulated by wounding the parent corm, for example, by making some sharp but shallow cuts on its base. To cultivate these plants, the cormels are split off and individually planted, right-side up, and a new plant will develop. The use of corms to propagate new plants in these ways does not involve any exchange of genetic information, and is referred to as vegetative propagation because the parent and progeny are genetically identical.

corm

views updated May 09 2018

corm In plants, an underground storage organ formed from a swollen stem base, bearing adventitious roots and scale leaves. Often it is renewed annually, each new corm forming on top of the preceding one. It may function as an organ of vegetative reproduction or in perennation.

corm

views updated May 21 2018

corm / kôrm/ • n. a rounded underground storage organ present in plants such as crocuses, gladioli, and cyclamens, consisting of a swollen stem base covered with scale leaves. Compare with bulb (sense 1), rhizome.

corm

views updated Jun 11 2018

corm An underground organ formed by certain plants, e.g. crocus and gladiolus, that enables them to survive from one growing season to the next (see illustration). It consists of a short swollen food-storing stem surrounded by protective scale leaves. One or more buds in the axils of scale leaves produce new foliage leaves and flowers in the subsequent season, using up the food stored in the stem. Compare bulb.

corm

views updated May 23 2018

corm Fleshy, underground stem that produces a plant such as the crocus. In most plants, new corms form on top of old ones, which last for one season. See also asexual reproduction

corm

views updated May 23 2018

corm The thickened, underground base of the stem of plants, often called bulbs, as, for example, taro and onion.

corm

views updated May 18 2018

corm In plants, an underground storage organ formed from a swollen stem base, bearing adventitious roots and scale leaves. Often it is renewed annually, each new corm forming on top of the preceding one. It may function as an organ of vegetative reproduction or in perennation.