Mesotrione a new herbicide for weed control in maize

Six field trials were conducted over three growing seasons to evaluate both preand postemergence applications of the recently developed herbicide mesotrione for weed control in maize As a preemergence treatment it provided excellent control of broadleaf weeds (>99 reduction in dry matter) but was poor on grass weeds (ca 80 reduction) However its combination with atrazine smetolachlor or acetochlor provided gt;93 reduction in grass and broadleaf weed dry matter Applications of mesotrione postemergence were very effective on broadleaf weeds (>94) but less so on grass weeds (ca 85) although several adjuvant combinations improved the efficacy against annual grass weeds A number of herbicide combinations were demonstrated to be effective for postemergence weed control Mesotrione did not cause any apparent damage to maize crops in any trial and grain yields were not significantly different from the standard treatments Recommended rates for postemergence use of mesotrione will be 7296 g/ha depending on soil type