Results 121 to 130 of about 14,562 (159)

On the volume-flow mechanism of phloem transport

Planta, 1973
A steady-state model of solution flow in a tubular semipermeable membrane is developed for an arbitrary distribution of solute sources and sinks along the translocation path. It is demonstrated that the volume-flow mechanism of phloem transport depends only on the two assumptions: 1.
J H, Young, R F, Evert, W, Eschrich
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Physiology of Phloem Transport

1995
Some deciduous trees transport considerable amounts of sugars in their vessels in spring. If a hole is drilled in the stem of a sugar maple (Acer saccharum) before budding, for example, a sugarrich “bleeding sap” flows out of the wood. How does this happen? Because of the secretion of sugar, especially sucrose, from storage cells via contact cells into
Hans Mohr, Peter Schopfer
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[21] Phloem transport

1989
Publisher Summary The term phloem transport refers to the flow of assimilates from their site of synthesis or storage to their site of consumption for methodological reasons and may be separated into three phases: phloem loading, long-distance transport, and phloem unloading.
Gabriele Orlich, Ewald Komor
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Ecophysiological Aspects of Phloem Transport in Trees

2014
The primary function of the phloem is the transport of assimilate products from mature leaves to other tissues. Here we examine this function from a whole tree perspective and relate it to assimilate production, tree water relations, and tree structure.
Teemu Hölttä, Maurizio Mencuccini, Eero Nikinmaa   +2 more
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Effects of Wounding on Transport in the Phloem

Journal of Experimental Botany, 1980
The problem dealt with was the nature of the mechanisms of the recovery of the phloem of Phaseolus vulgaris from the effects of wounds. The influence of root removal on the transport of [14C]sucrose and of fluorescein was followed both in the direction of the root and in the opposite direction, towards the intact shoot.
M. GERSANI, S. H. LIPS, T. SACHS
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Cadmium transport characteristics in the phloem of sweet potato

Plant Physiology and Biochemistry
Cadmium (Cd) pollution in farmland soil poses serious threats to human health. The Cd transport and accumulation in the aboveground tissues of sweet potato (Ipomoea batatas L.) variety "Fu Cai 18″ and the characteristics of phloem-mediated Cd transport were elucidated in this study. Sweet potato seedlings grown in hydroponics were analyzed.
Zanming, Chen, Xinyu, Zhao, Shiyuan, Zhang, Jianmin, Li, Guopeng, Zhu, Liang, Shi, Yahua, Chen   +6 more
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Phloem transport in gymnosperms: a question of pressure and resistance

Current Opinion in Plant Biology, 2018
Even in the highest trees, carbon is efficiently distributed from leaves to heterotrophic tissues like fruit, flowers and roots. This long-distance transport happens in the highly specialized sieve elements of the phloem. In gymnosperms, sieve element anatomy appears to be less suited for mass flow of phloem sap than that of angiosperms.
Liesche, Johannes, Schulz, Alexander
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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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Measuring Phloem Transport Velocity on a Tissue Level Using a Phloem-Mobile Dye

2019
Here we describe an in vivo dye-tracking method for measuring phloem transport velocity in seedlings, leaves and petioles and potentially other translucent plant tissues. The method requires measurement of the fluorescent signal of a phloem-mobile fluorescent dye using sensitive photo-sensors placed external to the plant.
Jessica A, Savage, Maciej A, Zwieniecki
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Origin of Cytokinins Transported in the Phloem

Physiologia Plantarum, 1979
AbstractThe origin of cytokinins in the exudate of Yucca inflorescences has been studied. A decrease in nucleotides of both isopenlenyladenine and zeatin was observed after removal of leaves as measured over a three day period. Removal of roots and the greater part of the rhizome resulted in a transient decline of isopenlenyladenincand zeatin ...
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