Uptake and Translocation of Bentazon with Additives

Abstract

Several experiments were conducted to determine the influence of temperature, relative humidity, leaf age, and additives on 14 C-bentazon [3-isopropyl-1 H -2,1,3-benzothiadiazin-(4)3 H -one 2,2-dioxide] uptake and translocation by redroot pigweed ( Amaranthus retroflexus L.), wild mustard [ Brassica kaber (DC.) L.C. Wheeler var. pinnatifida (Stokes) L.C. Wheeler] and soybeans ( Glycine max L. Merr. ‘Corsoy’). A water soluble linseed oil formulation enhanced absorption and translocation of the 14 C-label by redroot pigweed more than did emulsifiable linseed oil, petroleum oil, or a surfactant. The oil additives reduced the 14 C-label washed from the treated area of a leaf and increased absorption and translocation compared to bentazon applied alone. Low relative humidity and older leaves of redroot pigweed resulted in less 14 C-bentazon absorption than with high relative humidity or younger leaves. The addition of emulsifiable linseed oil reduced the influence of low relative humidity and leaf age upon 14 C-bentazon absorption. Comparative absorption and translocation of 14 C-bentazon was wild mustard > redroot pigweed > soybeans. Uptake and translocation of 14 C-bentazon by redroot pigweed was greater at 30 C than at 10 C.