No abstract

One of the obstacles to the production of cowpea is the intensity of weed infestations that may interfere with its productivity. The objective of this work was to evaluate the tolerance of cowpea, cultivar BRS Guariba, to the herbicides Linuromand Quizalofope-P Etílico, in the initial stage of development of the crop. The experiment was conducted in sequestrationsystem, emergency irrigation underfield conditions in experimental design with randomized blocks, nine treatments and four replicates. The treatments evaluated were: 50% Quizalofope-P-Ethyl; 50% of Linurom; 100% Quizalofope-P-Ethyl; 100% of Linurom; 50% Quizalofope-P-Ethyl+ 50% Linurom; 50% Quizalofope-P-Ethyl+ 100% Linurom; 100% Quizalofope-P-Ethyl+ 50% Linurom; 100% of Quizalofope-P-Ethyl+ 100% of Linurom,and Manual weeding (control). Visual evaluations of weed control, phytotoxicity, plant height, number of leaves and stem diameter were performed. The cowpea plants, BRS Guariba cultivar, presented high tolerance tothe herbicides 50% and 50% in the post-emergence applications. The herbicide 100% Linurom and the formulation of the Quizalofope-P-Ethyl + Linurom cause severe damage to the development of cowpea. The herbicides blended with 100% of Quizalofope-P-Ethyland 100% of Linurom potentiatesthe effect of the herbicides on the cowpea crop, causing the death of the plants.