Results 241 to 250 of about 14,195 (271)

Proton co-transport of sugars in phloem loading

Planta, 1977
Loading of (14)C-labelled sugars from the hollow petiole of Ricinus communis L. was stimulated by potassium and by low pH in that both the (14)C-activity and the sugar concentration of phloem sap collected from a nearby incision increased. A pH drop was observed in the solution perfusing a hollow petiole.
F, Malek, D A, Baker
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Phloem Loading and Unloading

1983
Since the classic discoveries of Malphighi, Hartwig and others it is known that in higher plants the photosynthetically derived assimilates are translocated, mostly in the form of sucrose, by specialized cells, the sieve tubes, to the growing tips and the storage organs.
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Evidence for two pathways of phloem loading

Physiologia Plantarum, 1994
The minor veins of small leaf discs, punched out of mature leaves and incubated in 14C‐sucrose solution, appear labeled in macro‐ and microautoradiographs. Discs with a labeled vein pattern and with labeled sieve tubes in microautoradiographs were found in Beta vulgaris, Vicia faba, Gomphrena globosa and Antirrhinum majus.
Walter Eschrich, Jorg Fromm
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Ecophysiology of phloem loading in source leaves

Plant, Cell & Environment, 1992
ABSTRACTThe nature of phloem loading of photosynthesis products – either symplastic or apoplastic – has been a matter of debate over the last two decades. This controversy was reconciled by proposing a multiprogrammed loading mechanism. Different modes of phloem loading were distinguished on the basis of the variety of plasmodesmatal connectivity ...
A. J. E. VAN BEL, Y. V. GAMALEI
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Plasmodesmata in the Phloem-Loading Pathway

1999
Twenty years ago, Brian Gunning began his analysis of the role of plasmodesmata in short-distance transport of assimilates to the phloem (Gunning1976) by stating that the “relevant evidence is both meagre and circumstantial” for a comprehensive discussion of the subject.
D. U. Beebe, W. A. Russin
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Amborella trichopoda, plasmodesmata, and the evolution of phloem loading

Protoplasma, 2010
Phloem loading is the process by which photoassimilates synthesized in the mesophyll cells of leaves enter the sieve elements and companion cells of minor veins in preparation for long distance transport to sink organs. Three loading strategies have been described: active loading from the apoplast, passive loading via the symplast, and passive ...
Robert, Turgeon, Richard, Medville
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Symplasmic Transport in Phloem Loading and Unloading

2013
The coordinated distribution of carbohydrates between different plant organs takes place in the phloem. Understanding how carbohydrates are loaded into and unloaded from this long-distance transport system is essential for our understanding of carbon allocation in plants and the mechanism of phloem transport.
Liesche, Johannes, Schulz, Alexander
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Sugar synthesis and phloem loading in Coleus blumei leaves

Planta, 1992
Sugar-synthesis and -transport patterns were analyzed in Coleus blumei Benth. leaves to determine where galactinol, raffinose, and stachyose are made and whether phloem loading includes an apoplastic (extracellular) step or occurs entirely within the symplast (plasmodesmata-connected cytoplasm).
R, Turgeon, E, Gowan
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Phloem Loading and Associated Processes

1975
Phloem loading is the process by which the major translocate species are selectively and actively taken up by the sieve tubes, especially in the minor veins of source regions. The entry of other solutes which may readily but passively move into the phloem is not considered to be part of phloem loading. One of the earliest and possibly the first mention
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Phloem loading from below

Nature Plants, 2021
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