abscission


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Related to abscission: abscission layer, abscission zone

ab·scis·sion

(ab-si'shŭn), Avoid the mispronunciation ab-si'zhŭn.
Cutting away.
[L. ab-scindo, pp. -scissus, to cut away from]

abscission

/ab·scis·sion/ (-sĭ´zhun) removal by cutting.

abscission

(ăb-sĭzh′ən)
n.
The act of cutting off.

abscission

[absish′ən]
Etymology: L, abscinere, to cut away
the process of cutting away, as in corneal abscission, removal of the prominence of the cornea.

abscission

An antiquated term for cutting; in modern medicine it has been replaced by the term excision, see there.

ab·scis·sion

(ab-sish'ŭn)
Cutting away.
[L. ab-scindo, pp. -scissus, to cut away from]

abscission

The act of cutting off.
Abscissionclick for a larger image
Fig. 4 Abscission . Abscission layer in a leafstalk.

abscission

the process by which plant organs are shed. This process occurs in the stalks of unfertilized flowers, in ripe fruits and in the base of the petiole of deciduous leaves in autumn, or in diseased leaves at any time. It is due to the formation of an abscission layer of thin-walled cells in the stalk base which rupture under strain produced by e.g. wind. A layer of cork forms beneath the abscission layer to seal the plant surface. Abscission is controlled by plant hormones present: a low concentration of AUXIN, high amounts of ETHYLENE, and (in some plants) a high concentration of ABSCISIC ACID all stimulate production of the abscission layer.

ab·scis·sion

(ab-sĭ'zhŭn)
Cutting away.
[L. ab-scindo, pp. -scissus, to cut away from]

abscission

removal of a part or growth by cutting.
References in periodicals archive ?
Except for a few families (Aizoaceae, Campanulaceae, Caryophyllaceae, Solanaceae, Portulacaceae, Lobeliaceae and Malvaceae), most of the flowers that showed initial wilting have been found to be insensitive to exogenous ethylene (Agavaceae, Compositae, Haemodoraceae, Iridaceae, Liliaceae, Umbelliferae, Gentianaceae and Euphorbiaceae) and most of the flowers showing initial abscission have been found to be ethylene sensitive (Acanthaceae, Boraginaceae, Geraniaceae, Gesneriaceae, Labiatae, Ranunculaceae, Rosaceae, Rubiaceae, Scrophulariaceae and Valerianaceae).
Some species, like Juglans nigra, use stress-induced leaf abscission during summer to increase the root-shoot ratio in order to maintain a more favorable water balance during summer droughts (Parker & Pallardy, 1985; Pallardy & Rhoads, 1993).
Selective fruit abscission by Juniperus monosperma as an induced defense against predators.
As the cells in the abscission layer become drier and more cork-like, it creates a barrier to the transport of minerals and other substances into the leaf.
As a result, there are three major limitations to this harvest approach: the market for stem-free cherries is untested and undeveloped, most sweet cherry orchards are not suited to mechanical harvesting, and not all sweet cherry varieties have the required abscission characteristics.
Leaves should be obtained during the fall as soon after abscission as possible.
After completing incubation period, abscission colonies were appeared on the plate 'surface.
Some authors have held that these features represent cone abscission scars, others that they are the result of branch abscission.