Quantitative relationships between growth and respiration

Red bean seedlings were grown from germination in the dark under three constant temperature coinditions (20, 25 and 30 C). Measurements of biomass and respiratory activities of their axes and cotyledons were made at one or two-day intervals. Two components of the axis respiration (constructive and maintenance respiration) were assumed, and they were evaluated separately. The constructive respiration coefficient was little affected by temperature, and was about 0.10 in every temperature treatment. The maintenance coefficient was on the other hand great affected by temperature, and the values were 0.036, 0.048 and 0.074 (mg C·mg C^?1·day^?1) in 20 C, 25 C and 30 C, respectively. The cumulative respiratory loss of carbon from the cotyledon during the experimental period was least in 20 C from among the three temperature conditions, and it was 40% of the total respiratory loss from the whole seedling. In 25 C and 30 C the losses were 47 and 46%, respectively. On the basis of these data concerning the respiratory losses and biomass changes, the carbon balance during the experimental period was examined, and some concepts of growth efficiencies were discussed.