This study was designed to determine performance of various strategies for control of winter annual weedsand summer annual weeds in a glyphosate-resistant no-till corn system. The study was conducted on aWeir silt loam with 1.5% organic matter and pH 6.0 at the Belleville Research Center. Fertilizer applied in2003 was150, 50 and 200 lb/A N, P2O5 and K2O, respectively, to an area that had been cropped tosoybean in 2002. DeKalb ‘DKC 60-17' glyphosate-resistant field corn was planted 1.5 inch deep at 28000seed/A into a no-till seedbed on May 24. Plots consisted of four rows with 30 inch row spacing, 25 ft longarranged in a randomized complete block design with three replications. Application timings were; followingharvest of previous crop (FALL), 14 days before planting (14DBP), and preemergence (PRE). Theherbicides were broadcast applied with a CO2 pressurized sprayer using 8003 flat fan tips at 40 PSI in 20GPA water. Monthly rainfall in inches was 3.4, 5.3, 1.1, 0.9, 0.4, 2.0, 2.7, 2.8, 4.8, 8.3, 1.9 and 4.2 inSeptember, October, November, December, January, February, March, April, May, June, July andAugust, respectively. Weed population per 0.25 m2 in the nontreated plots at mid-season was 3 giantragweed, 6 common ragweed, 1 giant foxtail and 1 common cocklebur.
展开▼
