Effects of Atrazine on Chlorophyll Retention in Corn Leaf Discs

Abstract

Corn (Zea mays L. ‘Dixie 18′) leaf discs were incubated in light or darkness in dilute solutions of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) with and without 6-furfurylamino-purine (kinetin). Kinetin decreased chlorophyll loss in light whereas atrazine had no effect. In darkness atrazine at a concentration of 5 × 10−8M increased clorophyll a retention in the absence of exogenous kinetin; but in the presence of 1.5 μg/ml of kinetin, the herbicide increased loss of chlorophyll a. Increasing the kinetin concentration to 15 μg/ml relieved the effect of 5 × 10−8M atrazine, but 10−7M atrazine increased chlorophyll loss. Higher concentrations of kinetin (150 and 1500 μg/ml) prevented all effects of atrazine. Factorial analysis revealed a highly significant interaction between atrazine and kinetin.