eCite Digital Repository

Alcoholic fermentation and malate metabolism in rice germinating at low oxygen concentrations

Citation

Avadhani, PN and Greenway, H and Lefroy, R and Prior, LD, Alcoholic fermentation and malate metabolism in rice germinating at low oxygen concentrations, Australian Journal of Plant Physiology, 5, (1) pp. 15-25. ISSN 0310-7841 (1978) [Refereed Article]


Preview
PDF
Restricted - Request a copy
632Kb
  

Copyright Statement

Copyright CSIRO 1978

DOI: doi:10.1071/PP9780015

Abstract

Germinating rice was exposed, in the dark, to low or zero O2 concentrations for 4-5 days by: (1) submergence under 4-5 cm of stagnant solution (3 ppm 02); (2) exposure to a N2 atmosphere;. or (3) submergence under solutions flushed with N2. These treatments completely inhibited root growth. Elongation of coleoptiles was stimulated in the stagnant solutions, but not in the N2 treatments. In most experiments, low O2 concentrations resulted in twofold to eightfold increases of malate concentrations in the shoots. Absence of 0, during exposure to Hi4C03-, for 30-60 min, inhibited C02 dark fixation. This inhibition was considerably smaller when seedlings had been raised in N2 rather than in air. Under aerobic conditions during fixation, excised shoots from seedlings raised in N2 fixed more C02 than shoots from seedlings raised in air. Malate always contained 70% or more of the total fixed 14C, irrespective of the 0, regime during germination and during I4CO2 fixation. Ethanol in stagnant solutions was shown to be formed by the rice seedlings, rather than by bacteria. Ethanol formation during one single day was 20-30-fold greater than the highest recorded amounts of malate in the seedlings. Alcoholic fermentation also responded quickly to changes in aeration regimes, indicating it was an important adaptive factor. Another likely adaptive feature was the high K+ concentration in shoots, even of seedlings grown in the complete absence of 0,. It is suggested that these high K+ concentrations have a function in maintaining turgor required for the rapid extension growth of the coleoptiles under low 0, concentrations.

Item Details

Item Type:Refereed Article
Research Division:Biological Sciences
Research Group:Plant Biology
Research Field:Plant Physiology
Objective Division:Environment
Objective Group:Land and Water Management
Objective Field:Farmland, Arable Cropland and Permanent Cropland Water Management
Author:Prior, LD (Dr Lynda Prior)
ID Code:72738
Year Published:1978
Web of Science® Times Cited:43
Deposited By:Research Division
Deposited On:2011-08-31
Last Modified:2011-09-28
Downloads:1 View Download Statistics

Repository Staff Only: item control page