Abstract Glyphosate is used frequently in agriculture, and sourgrass (Digitaria insularis (L.) Mez ex Ekman) has become one of the most problematic weeds in Brazil because of its resistance to this herbicide. One of the alternatives for sourgrass control is the use of graminicide alone or in mixture with glyphosate. Thus, this experiment was aimed at evaluating on the efficacy of glyphosate, clethodim, and the interaction glyphosate + clethodim, in glyphosate-resistant and susceptible biotypes of sourgrass. A completely randomized greenhouse experiment with four replications was repeated twice. The herbicide applications were performed at the initial stage (15 cm, BBCH 23). At 21 days after application (DAA), the herbicide visual control of weed and the weed dry matter was weighed. For the mixture of herbicides, the interaction between the herbicides was also verified as synergistic, antagonistic or additive. In general, the clethodim sprayed alone and the mixture controlled the resistant and susceptible biotypes at the initial stage. In the visual control, the interaction between glyphosate and clethodim showed synergistic effect at low and intermediate doses and an additive effect at the highest doses. For dry matter, the mixture had a synergistic interaction at all doses evaluated.

中文翻译：

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草甘膦和烯草醚单独和混合对酸草（Digitaria insularis）的影响

摘要 草甘膦在农业中经常使用，酸草（Digitaria insularis (L.) Mez ex Ekman）因其对这种除草剂的抗性而成为巴西最成问题的杂草之一。控制酸草的替代方法之一是单独使用禾本科杀螨剂或与草甘膦混合使用。因此，本实验旨在评估草甘膦、烯草酮以及草甘膦 + 烯草酮相互作用在抗草甘膦和敏感的酸草生物型中的功效。具有四次重复的完全随机温室实验重复两次。在初始阶段（15 cm，BBCH 23）进行除草剂施用。在施用后第 21 天 (DAA)，对杂草的目测除草剂和杂草干物质进行称重。对于混合除草剂，除草剂之间的相互作用也被证实是协同的、拮抗的或相加的。一般情况下，单独喷洒烯草酮和混合物在初始阶段控制了抗性和易感生物型。在视觉控制中，草甘膦和烯草酮之间的相互作用在低剂量和中剂量下表现出协同效应，在最高剂量下表现出累加效应。对于干物质，混合物在所有评估剂量下都具有协同作用。