Broadleaf weed control with pyrasulfotole/bromoxynil in comparison with other broadleaf herbicides

摘要

A study was conducted at the University of Idaho Research and Extension Center near Kimberly, Idaho to compare pyrasulfotole/bromoxynil to other herbicides for broadleaf weed control in "Alturas" spring wheat planted April 6, 2009, at 100 lb/A. Experimental design was a randomized complete block with four replications. Individual plots were 8 by 30 ft. Soil type was a Portneuf silt loam (26.4% sand, 65% silt, and 5.6% clay) with a pH of 8.1, 1.6% organic matter, and CEC of 14-meq/100 g soil. Herbicides were applied May 22 with a CO_2-pressurized bicycle-wheel sprayer using 11001 flat fan nozzles calibrated to deliver 10 gpa at 22 psi. Environmental conditions were as follows: air temperature 76 F, soil temperature 66 F, relative humidity 27%, wind speed 4 mph and 10% cloud cover. Kochia (KCHSC), common lambsquarters (CHEAL) and redroot pigweed (AMARE) densities averaged 3, 66 and 1 plants/ft2, respectively. Crop injury was evaluated visually 4, 49 and 69 days after application (DAA) on May 26, July 10, and July 30. Weed control was evaluated 28 and 69 DAA on June 19 and July 30. Grain was harvested August 17 with a small-plot combine.