Vapor Absorption and Translocation of Dinitroaniline Herbicides in Oats (Avena sativa) and Peas (Pisum sativum)

Abstract

Roots or shoots of oats (Avena sativaL. ‘Dal’) and peas (Pisum sativumL. ‘Early Perfection’) were exposed to vapors of14C-labeled benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), dinitramine (N4,N4-diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine), fluchloralin [N-(2-chloroethyl)-2,6 dinitro-N-propyl-4-(trifluoromethyl)aniline], oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide), profluralin [N-(cyclopropylmethyl)-α,α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine], and trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine). All of the dinitroaniline herbicides except oryzalin were absorbed by roots and shoots of germinating oats and peas. Some root-shoot translocation of the herbicides was observed in peas, but no shoot-root transport could be detected in either peas or oats. In peas,14C from root-absorbed benefin, fluchloralin, profluralin and trifluralin was detected in shoots, and14C from benefin and trifluralin was detected in cotyledons. In general, vapor absorption was correlated with rates of herbicide volatilization.