Residual Activity of Sulfentrazone Applied to Soybean on Cotton Crop in Succession

摘要

Weed resistance to glyphosate in agricultural production systems has led to the need of applying herbicides with different mechanisms of action. However, the persistence of these herbicides in the soil can harm the subsequent crop. This study aimed to assess the effect of the residual activity of the herbicide sulfentrazone applied in pre-emergence of soybean on cotton in succession. The experimental design was a randomized block design with five replications, with seven doses of sulfentrazone (0, 37.5, 75, 150, 300, 600, and 1,200 g ha-1). Cotton was sown at 112 days after herbicide application (DAA), with an accumulated precipitation of 637 mm during soybean cycle. Variables related to photosynthetic characteristics, phytointoxication, establishment, development, production components, and yield were assessed in both crops. The residual activity of sulfentrazone did not significantly interfere with the assessed variables in soybean but caused significant losses to cotton, which the recommended dosage (600 g ha-1) of the herbicide reduced cotton yield by 30%.