Stability test of bentazone and dicamba in water.

Abstract

A reduction in pesticide effectiveness, in general, may be due to hydrolysis. The rate of hydrolysis is dependent on pH, pesticide chemistry, length of time in the spray tank and water temperature in the spray tank. The exposure of the spray tank to sunlight will also impact the rate of hydrolysis. The present work describes stability test of bentazon and dicamba in water under different conditions, such as pH, presence or absence of sunlight and different temperatures. Stability of bentazon and dicamba aqueous solution was assessed by exposing aqueous samples to different temperatures, different pH (4, 7 and 10) and presence or absence of sunlight. The stability study under laboratory conditions revealed high stability of both compounds in aqueous solution pH 10, when exposed to sunlight or darkness. Dicamba was stabile at pH 7, while in aqueous solution pH 3 degraded 30% of initial concentration of dicamba. Bentazon degraded more that 50% after two weeks at pH 4 and 7.