ABSORPTION, TRANSLOCATION AND EXUDATION OF DICHLOBENIL AND VERNOLATE IN FIELD HORSETAIL

Abstract

The absorption, translocation and exudation of 14C-labelled dichlobenil (2,6-dichlorobenzonitrile) and vernolate (S-propyl-dipropylthiocarbamate) in field horsetail (Equisetum arvense L.) were examined in glasshouse and laboratory experiments. When applied as a vapor, more dichlobenil was absorbed than vernolate, irrespective of whether the roots or shoots were exposed to the herbicide vapors. Neither herbicide was translocated to the shoots after root exposure to the 14C-vapor, but a small amount was translocated to the roots after shoot exposure. When applied in aqueous solution to the roots and rhizomes, more 14C was recovered from the rhizomes of plants treated with vernolate. Both herbicides were concentrated at the rhizome nodes. Small amounts of 14C (less than 0.5% of the applied activity) were found in the guttation fluid and in root exudates.