| Abstract: | In a study of the relationship between carbon dioxide assimilation in the light, respiration in the dark, and temperature, the carbon dioxide content of air drawn over dwarf beans treated with lime sulphur or sulphur dust in light or darkness was continuously monitored coulometrically. Sulphur dust had only a negligible effect on carbon dioxide assimilation in the light or on respiration in the dark. Lime sulphur at 15 and 22°c also produced only small differences but at 30°c there were marked changes in net assimilation. Those treatments which caused changes in carbon dioxide assimilation in the light or respiration in the dark were directly associated with the degree of damage estimated visually. The method may be valuable for the detection of phytotoxic effects of other fungicides and insecticides. |
