Cyprosulfamide Safens Isoxaflutole in Sweet Corn (Zea mays L.)

There is little published information on the sensitivity of sweet corn to the PRE and POST application of isoxaflutole + cyprosulfamide. Four field trials were conducted during 2010 and 2011 in Ontario, Canada, to determine the sensitivity of 'Merit', 'GH 4927', 'BSS 5362', and 'GG 741' sweet corn hybrids to the PRE and POST application of isoxaflutole alone or in combination with cyprosulfamide. Isoxaflutole applied PRE or POST at 105 and 210 g a.i./ha caused as much as 12% visual injury, 18% reduction in height. and 24% reduction in marketable yield of some sweet corn hybrids evaluated. Isoxaflutole + cyprosulfamide applied PRE or POST at 105 and 210 g.ha(-1) caused up to 7% initial injury in some sweet corn hybrids but the injury was transient with no effect on sweet corn height, cob size, and yield. Isoxaflutole applied POST was more injurious to sweet corn than when applied PRE; however, there was no differences in sweet corn injury between the PRE and POST applications of isoxaflutole + cyprosulfamide. Based on these results, there is potential for use of isoxaflutole + cyprosulfamide applied at 105 g a.i./ha in 'Merit', 'GH 4927', 'BSS 5362', and 'GG 741' sweet corn hybrids.