STUDIES ON THE METABOLISM OF CEREAL GRAINS: I. THE OUTPUT OF CARBON DIOXIDE BY WHEAT GRAINS DURING ABSORPTION OF WATER AND GERMINATION

Abstract

The course of respiration during the early stages of germination is recorded for a number of varieties of bread and durum wheats. Germination is marked by three consecutive respiratory stages which are characterized by the rate at which the acceleration in carbon dioxide output occurs. These stages are (a) a slow rate of acceleration, (b) an increased rate followed by a decreasing rate, and (c) a final uniform and relatively high rate. Water absorption rate under the experimental conditions used does not appear to affect these respiratory stages. The infection of germinating grains by fungi reduces their respiration. Possible physiological explanations of the respiration stages are discussed.