STUDY OF RESPIRATION IN HEALTHY AND MOSAIC-INFECTED TOBACCO PLANTS

Abstract
The paper describes the apparatus and method for comparing the respiration of entire healthy and mosaic-diseased tobacco plants from the time of inoculation until the appearance of the mottling disease. The same plants were used throughout the period of each expt. The respiration rate of the diseased plants and healthy plants remained at the same level until the disease became systemic. When the clearing of the veins was apparent, the respiration rate of the diseased plants rose rapidly, followed by a decrease until in the older plants it became approx. equal to that of the healthy plants by the time that the mosaic mottling had developed. The % increase in respiration rate was approx. 50% higher than the rate of the corresponding healthy plants.