학술논문

Response to Anoxia in Rice and Wheat Seedlings: Changes in the pH of Intracellular Compartments, Glucose-6-Phosphate Level, and Metabolic Rate.
Document Type
Academic Journal
Author
Menegus F; Istituto Biosintesi Vegetali, CNR, Via Bassini 15, 20133 Milano, Italy.; Cattaruzza LMattana MBeffagna NRagg E
Source
Publisher: American Society of Plant Biologists Country of Publication: United States NLM ID: 0401224 Publication Model: Print Cited Medium: Print ISSN: 0032-0889 (Print) Linking ISSN: 00320889 NLM ISO Abbreviation: Plant Physiol Subsets: PubMed not MEDLINE
Subject
Language
English
ISSN
0032-0889
Abstract
(31)P nuclear magnetic resonance spectroscopy was used to measure intracellular pH in living tissues. Oxygen deprivation caused fast cytoplasmic acidification from pH 7.4 to 7.0 in shoots of rice, Oryza sativa L. var arborio, a species highly resistant to anoxia. Acidification was complete after 10 minutes of anoxia. Alkalinization of both cytosplasm and vacuole followed thereafter. In the anoxia intolerant wheat shoots, Triticum aestivum L. var MEK, the same treatment caused a sharper cytoplasmic acidification, from pH 7.4 to 6.6, which occurred during a period of 2 hours. Cytoplasmic acidification continued with progress of anoxia and there was no vacuolar alkalinization comparable to the one observed in rice. In wheat oxyen, withdrawal also caused the reduction of both glucose-6-phosphate level and of metabolic rate. It also induced heavy losses of inorganic phosphate from tissues. Conversely, in rice, glucose-6-phosphate level and metabolic rate were increased and inorganic phosphate leakage from tissues was completely absent. These results are discussed in relation to the mechanisms of plant resistance to anoxia.