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n. Botany
A complex branched carbohydrate commonly associated with sieve areas of sieve elements.

[From Latin callōsus, callous; see callous.]


(Botany) a carbohydrate, a polymer of glucose, found in plants, esp in the sieve tubes


(ˈkæl oʊs)

1. having thickened or hardened spots, as a leaf.
[1860–65; < Latin callōsus]
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References in periodicals archive ?
pollen which showed present abnormalities pollen tube as bifurcated monosphonic pollen tube, pollen tube with a wavy structure, pollen tube due to cytoplasm deposition and wall swelling, pollen tube with thickened walls, pollen tube with callose formation at its tips and Callose plugs formed in pollen tube cytoplasm, but this research did not mention percentage of each type.
Exine pattern determination was originally attributed to callose (e.
In a genetic screen we identified gain-of-function mutations in a locus that codes for a CALLOSE SYNTHASE isoform CALS3.
Sucrose utilization via invertase and sucrose synthase with respect to accumulation of cellulose and callose in wheat roots under oxygen deficiency.
2B), male also with a pair of yellow callose spots close to posterior margin of sternite VIII.
Jagels and Garner (1979) observed the variation in callose deposition in the ligules of Selaginella.
Japan Science and Technology Corporation (Saitama, Japan), National Institute of Agrobiological Sciences (Ibaraki, Japan), and Forestry and Forest Products Research Institute (Ibaraki, Japan) have patented a method for producing non-cellulosic callose fiber by using plant protoplast, which imposes less burden to the environment with reduced energy consumption compared to conventional natural fibers is provided; it comprises the addition of an inorganic ion to a plant protoplast cultivation system, which leads the plant protoplast to produce non-cellulosic callose fiber.
enhanced lignification, polymer cross-linkage, and callose deposition), disruption of [Ca.
After a systematic screening for Al toxicity, Cayenne and Soft Touch were selected, since they showed the most Al-resistant and Al-sensitive characteristics, respectively (through their root-growth response to Al, Al content, and callose accumulation in the root tips).
Callose staining indicates numerous cytoplasmic connections between bundle sheath cell prolongations and neighboring non-vascular cells.
By October, Cummings Carson said, callose tissue should have formed around some canker margins if the introduced hypovirulent strain is reproducing.
After the dissolution of the callose wall, the sporopollenin wall begins to form.