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Callose is commonly used term for β (1–3)-linked D-glucan. It is plant derived linear polysaccharides that consist of hundreds of (1–3) β glycosidic connected glucose subunits. In comparison with cellulose that have long chain of thousands of 1–4 linked glucose residues with a crystal-like structure, Callose have relatively helical shapeless structure with 1–3 glycosidic bounds glucose residues [20].

In plants, Callose has been produced by specialized cells at different developmental stages of the cell wall, especially in cell plate formation during cell division, vascular bundles, pollen wall exine, etc. Interestingly, the Callose are deposit in the region surrounded the plasmodesmata in cell wall and then subsequently degraded, thus play important role in regulation of symplast transportation. Callose is also responsible for the formation and closing of pores in sieve plates in vascular bundles and play important role in an intracellular communication in plants. Callose is biosynthesized in plants through an enzyme known as Callose synthases and degraded by (1–3)-β-glucanase. Callose also play role in plant defense against unfavorable environmental conditions and phytopathogens [21, 22].