Rates of Photosynthesis and Respiration in Relation to Stomatal Movements in Leaves Treated with α-Hydroxysulphonate and Glycollate

Abstract

Leaves of tobacco and Xanthium pennsylvanicum were treated with solutions of α-hydroxysulphonate and glycollate in normal air. During the treatment with α-hydroxysulphonate the intercellular-space carbon dioxide concentration of the leaves increased owing to a decrease in photosynthetic activity. It seems probable that these increases in internal carbon dioxide concentration were the cause of stomatal closure, because when treated leaves were flushed with carbon dioxide free air the stomata reopened. Experimental results also showed that the accumulation of glycollate, resulting from treatment with α-hydroxysulphonate, could not be held responsible for stomatal closure because treatment with glycollate alone had no influence on either the internal carbon dioxide concentration or on the stomata of the leaves.