Uptake and Translocation of Bentazon with Additives

Abstract

Several experiments were conducted to determine the influence of temperature, relative humidity, leaf age, and additives on14C-bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4)3H-one 2,2-dioxide] uptake and translocation by redroot pigweed (Amaranthus retroflexusL.), wild mustard [Brassica kaber(DC.) L.C. Wheeler var.pinnatifida(Stokes) L.C. Wheeler] and soybeans (Glycine maxL. Merr. ‘Corsoy’). A water soluble linseed oil formulation enhanced absorption and translocation of the14C-label by redroot pigweed more than did emulsifiable linseed oil, petroleum oil, or a surfactant. The oil additives reduced the14C-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 less14C-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 upon14C-bentazon absorption. Comparative absorption and translocation of14C-bentazon was wild mustard > redroot pigweed > soybeans. Uptake and translocation of14C-bentazon by redroot pigweed was greater at 30 C than at 10 C.