Evaluation of two-pass versus single-pass corn herbicide programs for crop phytotoxicity andweed control, Ames, IA, 2003

摘要

Thepurpose of this study was to evaluate the effectiveness of two-pass and single-pass corn herbicideprograms for crop phytotoxicity, weed control and yield. The soil was a Canisteo, Nicollet, Clarion andWebster clay loam with a pH 6.8 and 5.3% organic matter. The experimental design was a randomizedcomplete block with three replications and plots were 10 by 25 ft. The 2002 crop was soybean. Tillageincluded a fall chisel plowing and a spring field cultivation. Fertilization included 127 lb/A actual N appliedas urea. Crop residue on the soil surface was 35% at planting. “Dekalb hybrid DKC 58-24” corn wasplanted 1.5 inches deep on May 18, at 27,700 seeds/A in 30-inch rows. Preemergence (PRE) treatmentswere applied on May 21 at 20 gpa and 25 psi using flat fan nozzles.