Effect of Atrazine on Physiological Processes in Leaves

Abstract

We fed 2-chloro-4-(ethylamino)-6-(isopropylamino-s-triazine (atrazine) through the base of excised leaves of atrazine-tolerant and -susceptible species. Atrazine suppressed CO2 uptake in all species. This was shown to be due primarily to inhibition of the photosynthetic reactions and only to a slight extent to the stomatal closure caused by atrazine. Atrazine did not cause stomatal closure in CO2-free air. Atrazine inhibited photorespiration but did not inhibit oxidation of externally supplied glycolate. It had no effect on dark respiration.