Ecophysiological Aspects of Phloem Transport in Trees
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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. We argue that the turgor and osmotic pressures driving flow in the phloem are determined by these factors. An example calculation of these interactions is presented. The generalizations and possible shortcomings of the Münch flow hypothesis, the simplest theoretical framework used in describing phloem transport, are also discussed.
KeywordsSugar Concentration Turgor Pressure Sieve Tube Sieve Element Xylem Water
T. Hölttä received funding from Academy of Finland project #1132561. M. Mencuccini received funding from NERC grant number NE/I011749/1.
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