callus


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callus:

see corns and callusescorns and calluses,
thickenings of the outer layer of skin where there is irritation or constant pressure. Corns are cone-shaped with their points protruding into the dermis, or inner layer of skin. They usually have hard, shiny surfaces surrounded by red, painful areas.
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Callus

 

(1) Tissue formed in plants on the surface of a wound (cracks, taps, the bases of cuttings, and areas of concrescence of stock and scion). A callus promotes the healing of wounds. Consisting of thin-walled parenchymal cells, a callus develops when there is cell division of any living tissue of the plant (cambium or phloem) in the peripheral zone of the pith, lying next to the protoxylem. Adventitious roots and buds, particularly with grafting, often develop in the callus. (2) Corpus callosum, an accumulation of callóse that obstructs the sieve plate when the sieve tubes of the phloem age. Use of the term in this sense is obsolete.


Callus

 

a thickening of the horny layer of skin as a result of constant pressure or friction. Calluses usually appear on the palms, soles, and other parts of the body that are in constant contact with tough surfaces. The cracks formed on the surface of a callus may hinder one’s ability to work, and they can also be portals of entry for pyogenic microbes, resulting in such conditions as erysipelatous inflammations and phlegmons.

callus

[′kal·əs]
(botany)
A thickened callose deposit on sieve plates.
A hard tissue that forms over a damaged plant surface.
(medicine)
Hard, thick area on the surface of the skin.

callus

1. an area of skin that is hard or thick, esp on the palm of the hand or sole of the foot, as from continual friction or pressure
2. an area of bony tissue formed during the healing of a fractured bone
3. Botany
a. a mass of hard protective tissue produced in woody plants at the site of an injury
b. an accumulation of callose in the sieve tubes
4. Biotechnology a mass of undifferentiated cells produced as the first stage in tissue culture
References in periodicals archive ?
7 plants per gram of callus in 42 tropical lines, including the BR 451 variety, in MS medium, in the absence of growth regulators; although, the authors did not specifically mentioned the frequency of plant regeneration for this variety.
BAP and NAA hormone combination is one of the most effective combinations for acquiring shoot and callus formation (Pavalek - Kozlina et al.
As the objective of this work was producing pigments in callus culture, we evaluated three main aspects in the cultivation (percentage of callus formation, color and callus appearance) to select the best culture media for experimental sequence as shown in Table 1.
Salt-tolerant MR219 callus was produced, screened and directly selected according to the modified method reported by Queiros et al.
Keeping in view the importance of cotton tissue culture and its usage in Plant Biotechnology, the present study is aimed to screen the callogenesis and regeneration potential of some selected cotton varieties for the development of an optimal in vitro protocol through callus or shoot tip culture.
Ten days old lab grown seedlings were used as explant source for callus induction.
In September we verified the smallest percentage of callus using coconut fiber (8%); when using sphagnum in the same month, 100% of the layering showed callus.
The culture medium compositions for induction of callus were prepared as MS medium containing different concentrations (see detail in Results section) of phytohormones including 6-benzylaminupurine (BAP); kinetin (Kn); 2,4-dichlorophenoxy acetic acid (2, 4-D); [?
At primary fracture with displacement the deformation of the site of fracture is clearly visible, and at refracture it is less expressed because of presence of periosteal callus.
Embryo excision and callus induction: Seeds were threshed from spikes and surface-sterilization using 70% (v/v) ethanol for 50 second with continuous stirring increased the efficiency of sterilization, then 3% (v/v) sodium hypochlorite solution was used to disinfect for 20 min, and finally washed five to six times with autoclaved deionized double distilled water.
The callus ,,s morphological characters were recorded.