Translocation of the Herbicide Dicamba in Purple Nutsedge, Cyperus rotundus

Abstract

Pairs of nutsedge plants connected by rhizomes were planted, each in a separate pan, without cutting the rhizomes. One plant within each pair was treated with 5.7 kg of dicamba per hectare seven days later. Ten days after treatment, the treated plants and those plants attached to them by rhizomes were harvested separately and analyzed by gas chromatography. The attached plants were found to contain 6 per cent as much dicamba as did the directly treated plants. The suspected metabolites, 3,6‐dicblorosalicylic acid, 3,6‐dicblorogentisic acid and 5‐HO‐dicamba, were not detected.

Dicamba Uptake, Translocation, Metabolism, and Selectivity

“…and many other broadleaf weeds in cereal crops.s-" Rapid metabolism of dicamba has been reported in two resistant sp-ecies, wheat (Triticum uulgare L.) and bluegrass (Poa pratensis L.) (1). In purple nutsedge (Cyperus rotundus L.), a susceptible species, no metabolism of the herbicide was detected (4,5). In Canada thistle (Cirsium arvense (L.) Scop.)…”