Control of ryegrass in corn requires integrated management

Among the weeds that are difficult to control in corn cultivation, ryegrass (Lolium multiflorum) stands out for its resistance to different herbicides. According to Marcieli Piccin, Market Development Representative at Bayer, and Daniel Fernando Kolling, an agricultural engineer, this plant has been identified by the Herbicide Resistance Action Committee as resistant to the action mechanisms of EPSPs (glyphosate), ACCase inhibitors (clethodim), and ALS (nicosulfuron). In addition to multiple resistance, ryegrass produces a large amount of seeds with short dormancy, which facilitates the re-infestation of cultivated areas. Management must be planned in a systemic way, considering the cycles of the crops preceding corn. For example, straw on the soil acts as a physical barrier and, in some species, exerts an allelopathic effect that can reduce the germination of ryegrass. Another fundamental strategy is crop rotation, which broadens the spectrum of action mechanisms employed in ...