Journal article

Publication year: 1993

Pages: 155-161

Journal: Journal of Plant Nutrition and Soil Science

Volume number: 156

Issue number: 2

ISSN: 0044-3263

DOI Link: https://doi.org/10.1002/jpln.19931560210

Publisher: Wiley-VCH Verlag

Abstract: 
Net release and net uptake of sugars by roots of intact maize (Zea mays cv. Blizzard) and field bean (Vicia faba L. cv. Alfred) were studied at micromolar external sugar concentrations that are relevant to the rhizosphere. Besides various sugars not further characterized there was net release of glucose, fructose, sucrose, arabinose, ribose, and galactose. The net release of these sugars into the root medium (0.1 mM CaSO4) was stimulated by the protonophore CCCP (10 muM), the sulfhydryl reagent NEM (300 muM), the specific inhibitor of plasmalemma H+ ATPase vanadate (0.5 mM), and by the inhibitor of the glucose carrier phlorizin (2 mM). Net uptake of glucose, fructose, and arabinose from 10 muM external concentrations was inhibited by these substances. Stimulation of net release and inhibition of net uptake was most pronounced for glucose. Sucrose added to the root medium was hydrolyzed by invertase activity leading to glucose and fructose uptake by roots. It is concluded that the retention of sugars by plant roots is not only determined by plasmalemma permeability but is also controlled by the H+ electrochemical gradient established by ATPase activity (retrieval mechanism). The proton gradient drives a sugar/H+ cotransport system that is selective for glucose but may also transport other sugars, particularly in the absence of glucose.

Harvard Citation style: Mühling, K., Schubert, S. and Mengel, K. (1993) Role of Plasmalemma H+ ATPase in Sugar Retention by Roots of Intact Maize and Field Bean Plants, Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde, 156(2), pp. 155-161. https://doi.org/10.1002/jpln.19931560210

APA Citation style: Mühling, K., Schubert, S., & Mengel, K. (1993). Role of Plasmalemma H+ ATPase in Sugar Retention by Roots of Intact Maize and Field Bean Plants. Journal of Plant Nutrition and Soil Science = Zeitschrift für Pflanzenernährung und Bodenkunde. 156(2), 155-161. https://doi.org/10.1002/jpln.19931560210