callose


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cal·lose

(kal'ōs),
A linear 1,3-β-d-glucan formed by certain enzymes from UDP-glucose, differing from cellulose (a β-1,4-glucan formed from GDP-glucose) and starch amylose (an α-1,4-glucan formed from ADP-glucose). Found in certain plant cell walls.

callose

a thick CARBOHYDRATE plant material deposited in the pores of sieve plates in response to damage, disease or simply over a period of time, resulting in a blockage of the SIEVE TUBE. Callose is also present in the walls of fungal hyphae.
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5-3 cm, base nearly round, truncate or slightly cuneate, margins with short and triangular teeth, each ending in a callose papilla, apex acuminate to cuspidate, green and often suffused with purple and slightly puberulous on the abaxial surface, venation brochidodromous, secondary veins 6-8 pairs, ascending in ca.
The gametophytic genomic component and a callose wall are missing in the orbicule model and yet a patterned accumulation of sporopollenin with similar ornamentation to the pollen wall (Hesse, 1986; Huysmans et al.
When wounding of the phloem occurs, the sieve tubes apparently synthesize a polysaccharide called callose, which plugs the sieve plate and reduces the flow.
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.
A reduction in large callose deposits surrounding haustoria of Peronospora parasitica infecting Arabidopsis thaliana was indirectly achieved in transgenic plants not accumulating Salicylic acid (SA) by expression of the enzyme salicylate hydroxylase (Donofrio and Delaney , 2001).
Leaves 2, reduced to tubular sheaths; upper leaf sheath up to 15 cm long, membranous-translucent, loose but not inflated, friable, often splitting adaxially, stramineous to pale grayish brown, apex obtuse to subacute, not callose, tooth-like projection (mucro) absent or very short; lower leaf sheath much shorter than upper, membranous, dark grayish brown to almost black.
Elytra moderately convex, oval-elongate, not denticulate at shoulder, more or less widened posteriorly and more or less strongly callose on preapical declivity, more or less diffusedly pubescent or nearly glabrous, usually rather dull; striae generally fine and feebly or not at all crenulate; interstices flat, rarely convex, more or less distinctly punctured; epipleura strong, elongately bristled at least at two basal thirds.
enhanced lignification, polymer cross-linkage, and callose deposition), disruption of [Ca.
Aluminum resistance is usually assessed in seedling-based assays, either by quantifying root elongation or apical callose concentrations, or by staining root apices with hematoxylin (Kerridge and Kronstad, 1968; Polle et al.
Ultrastructural changes and localization of chitin and callose in compatible and incompatible interactions between carnation callus and Fusarium oxysporum.
Weller SG, Ornduff R (1989) Incompatibility in Amsinckia grandiflora (Boraginaceae): distribution of callose plugs and pollen tubes following inter- and intramorph crosses.
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).