Eficiência de controle de populações de leiteiro (Euphorbia heterophylla L.) com a utilização de herbicidas

Abstract

Efficient control of wild poinsettia (Euphorbia heterophylla) populations is crucial for effective weed management in agricultural crops. Wild poinsettia, known for its competitive capacity and prolificacy, becomes a significant threat to crops, negatively affecting crop yields. However, the development of herbicide resistance in weeds has become a growing concern, making it essential to understand the efficacy of control at different rates and growth stages. This study evaluated the efficacy of chemical control of two wild poinsettia biotypes in applications of four herbicides. The experiments were carried out in a completely randomized design, with four replicates, in a 2 x 4 x 7 factorial scheme. The first factor consisted of two wild poinsettia biotypes; the second factor consisted of the four herbicides (named A, B, C, D); and the third factor was different proportions of the dose recommended dose of the herbicides (0, 12.5, 25, 50, 100, 200 and 400%). Differences in control were observed between the herbicides. The levels of control increased as the doses increased, but for one of the biotypes satisfactory control was only achieved with the highest doses (200 and 400%). These results reinforce the need for integrated management strategies, including the rotation of mechanisms of action and cultural practices, to contain the evolution of resistance and ensure the sustainability of agricultural systems.