Acetanilide Herbicides for Yellow Nutsedge (<i>Cyperus esculentus</i>) Control in Corn (<i>Zea mays</i>)

Abstract

Studies were undertaken to evaluate the phytotoxicity to yellow nutsedge ( Cyperus esculentus L.), length of soil persistence, and tolerance of corn ( Zea mays L.) to several acetanilide herbicides. The herbicides involved were alachlor [2-chloro-2′,6′-diethyl- N -(methoxymethyl)acetanilide]. diethatyl [ N -(chloroacetyl)- N -(2,6-diethylphenyl)glycine], H-26910 [ N -(chloroacetyl)- N -(2-ethyl-6-methylphenyl)glycine-1-methylethyl ester], metolachlor [2-chloro- N -(2-ethyl-6-methylphenyl)- N -(2-methoxy-1-methylethyl)acetamide], Ortho 19790 [1-(chloroacetyl)-2,2-dimethyl-3-oxa-1-azaspiro-[4, 5]-decane], and Vel 5052 [2-chloro- N -(2,6-dimethylphenyl)- N -(1,3-dioxolan-2-ylmethyl)acetamide]. Most of these herbicides were equally active on yellow nutsedge in solution culture; only metolachlor and Vel 5052 were significantly more active than H-26910. Metolachlor and alachlor were the most toxic to yellow nutsedge in greenhouse and field experiments. Metolachlor persisted the longest of the herbicides in the field after spring applications. The tolerances of corn differed little among the herbicides at expected use rates.