Translocation of Atrazine: Accumulation Versus Passage Through Petioles

Abstract

Atrazine [2-chloro-4-(ethylamino)-6-(isopropyl-amino)-s-triazine] applied to the soil of potted tomatoes (Lycopersicon esculentumMill. ‘John Baer’) reached its maximum concentration in the xylem exudate collected from the stumps of detopped plants in 6 to 8 hr but continued to accumulate in the petioles for 36 hr. An atrazine concentration of 3.8μg/g fresh weight of petiole at 12 hr after treatment was approximately the same as the maximum concentration of atrazine in the xylem exudate indicating that atrazine had accumulated extensively in tissues outside of the xylem vessels.