Relative Phytotoxicities of Dinitroaniline Herbicides

The relative phytotoxicities of 12 substituted dinitroaniline herbicides to soybeans [ Glycine max (L.) Merr ‘Corsoy’], velvetleaf ( Abutilon theophrasti Medic.), and either giant foxtail ( Setaria faberi Herrm.) or foxtail millet [ Setaria italica (L.) Beauv.] were compared under greenhouse and laboratory conditions. In these studies, dinitramine ( N 4 , N 4 -diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine) was most toxic to each species. Dinitramine, trifluralin (α,α,α-trifluoro-2,6-dinitro- N,N -dipropyl- p -toluidine), and BAS-3921 H [ N -propyl- N -(2-chloroethyl)-α,α,α-trifluoro-2,6-dinitro- p -toluidine] were most inhibitory of soybean shoot growth, while oryzalin (3,5-dinitro- N 4 , N 4 -dipropyl-sulfanilamide), dinitramine, and BAS-3921 H were most inhibitory of root growth. Similarly, dinitramine, oryzalin, nitralin [4-(methylsulfonyl)-2,6-dinitro- N,N -dipropylaniline], and BAS-3921 H inhibited velvetleaf shoot growth; and oryzalin, dinitramine, chlornidine [2,6-dinitro- N,N -di(2-dichloroethyl)- p -toluidine], nitralin, and GS-39985 ( N-n -propyl- N -tetrahydrofurfuryl-4-trifluoromethyl-2,6-dinitroaniline) reduced root growth. All of the herbicides except oryzalin and nitralin inhibited foxtail millet shoot growth, while all of the herbicides reduced root growth.