Importância de adjuvantes na eficiência de controle de Amaranthus viridis L.

Abstract

The objective of this study was to identify the importance of adjuvants, when associated with Glyphosate and 2,4 D herbicides, in the control efficiency of Amaranthus viridis L. in shade 50%. The experimental design employed was completely randomized, with five treatments and three replications. After 30 days of germination, the weed was subjected to desiccation, using the herbicides Glyphosate: ZAPP QI 620 and 2,4-D: U46 Prime, at dosages of 2.5 L/ha and 1.25 L/ha of the commercial product, respectively, in a spray volume of 400 L/ha, together with five different combinations of adjuvants corresponding to the treatments (Iharol gold, H2 Dessek, H2 Alvo, H2 Alvo + Agrofix, H2 Dessek + Agrofix). The adjuvant Iharol gold showed lower control efficacy in the first 6 hours, remaining lower until the 22 hours of evaluation. The use of foliar fertilizers as adjuvants showed greater ease of penetration, with emphasis on the performance of Dessek with 47.6% of control in the first 6 h. All adjuvants were efficient in controlling Amaranthus viridis L., but in the first hours Dessek showed the highest control efficiency and Iharol the least efficient.