Inhibition of Lipid Synthesis by Certain Herbicides

Thirty herbicides were tested for possible effects upon the incorporation of radioactivity from malonic acid-2-14C into lipid by excised hypocotyls of hemp sesbania (Sesbania exaltata (Raf.) Cory). Concentrations of 1 to 20 mg/L were used. Inhibition was caused by 3-nitro-2,5-dichlorobenzoic acid (dinoben), 2-chloro-N,N-diallylacetamide (CDAA), 2-chloroallyl diethyldithiocarbamate (CDEC), 7-oxabicyclo(2.2.1)heptane-2,3-dicarboxylic acid (endothall), 2,6-dichlorobenzonitrile (dichlobenil), 3,5-diiodo-4-hydroxybenzonitrile (ioxynil), and pentachlorophenol (PCP). At 1 mg/L, stimulation was caused by 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), 4-amino-3,5,6-trichloropicolinic acid (picloram), and 3-amino-2,5-dichlorobenzoic acid (amiben).