This study aimed to evaluate the effect of the tank mixture of the herbicide nicosulfuron with the insecticide chlorpirifos on the maize hybrid P30F80, weeds, and fall armyworm. The experiment was arranged in a randomized complete block design, in a 5x2+3 factorial scheme and four replications. The first factor consisted of nicosulfuron doses (0, 10, 20, 30, and 40 g ha-1) + atrazine (1.200 g ha-1) + oil (900 g ha-1) and the second of doses of the insecticide chlorpirifos (0 and 240 g ha-1). Three additional treatments were evaluated: two controls, with and without weeding, both without insecticide, and one control with weeding and insecticide. The interaction between the doses of nicosulfuron and chlorpirifos in the control of the fall armyworm was not significant. The chlorpirifos-nicosulfuron tank mixture was non-selective for the maize hybrid P30F80, reducing the number of ears and maize grain yield. Chlorpirifos did not interfere in the efficiency of weed control by the herbicides 14 and 28 days after application of these products. However, the toxicicity caused to the maize plant by the chlorpirifos-nicosulfuron tank mixture contributed to reducing the crop control of Ipomoea grandifolia and Brachiaria decumbens by maize.
nicosulfuron; chlorpirifos; interaction
