phloem


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phloem

a transport tissue characterized by the presence of sieve tubes, companion cells and phloem parenchyma cells, found in the VASCULAR BUNDLES of higher plants. Phloem functions in the transport of dissolved organic substances (e.g. sucrose) by TRANSLOCATION.
References in periodicals archive ?
Areas of the tissues were obtained as follows: the adaxial surface of the epidermis, the abaxial surface of the epidermis, the chlorophyll parenchyma, the sum of the phloem areas, the average phloem area in one vascular bundle, the sum of the areas of the vascular bundle sheaths, the sum of the areas of the vascular bundles, the sum of the areas of the xylem, the average xylem area in one vascular bundle, the sum of the area of fibers, the average fiber area in one vascular bundle, and the whole leaf area captured in the image using square micrometers as the measurement unit.
The sucrose available for exporting from mesophyll cells is transported through the phloem to the sink organs, where it can be stored as starch in amyloplasts or converted to hexoses (LEMOINE et al., 2013) by invertase (acidic and neutral isoforms) and sucrose synthase (susy) enzymes (STURM; TANG, 1999; WINTER; HUBER, 2000; WELHAM et al., 2009).
Phloem-sucking insects, with long stylets, induce phloem hypertrophy (Figs.
Branch girdling blocks the phloem flow, making it more nutritive for offspring and future colonizers.
Collection of pure phloem sap from wheat and its chemical composition.
They showed that in contrast to the late stage, during this early stage young phloem cells (protophloem) are initiating and organising the primary (procambial) stage of radial growth.
Furthermore, in the cultivar Revolucion, Finetti Sialer (1990) observed that during the expansion of the feeding site, adjacent phloem cells were displaced or incorporated into the syncytium.
Infection by GLRaVs is limited to the phloem, (11) and results in the degeneration of primary phloem tissues in shoots, leaves, and clusters.
Veins are collateral, with the xylem located upper side and phloem located lower side.
In mature sugarcane stems, sucrose transport follows a predominantly symplastic movement when moving from the phloem into the storage parenchyma cells (Lingle, 1989; Rae et al., 2005; Patrick et al., 2013).