Efficacy of nicosulfuron isolated and associated with atrazine on the weeds management of corn

Abstract

The potential yield of corn may be affected by weed interference. The aim of this research was evaluate the chemical control of weed in fields of corn (BRS 1035), with sub lethal rates of nicosulfuron associated with atrazine in order to reduce doses without lose large spectrum of action in the control of weed community. The herbicides treatments were: nicosulfuron at 20, 40 e 60 g ha^-1, nicosulfuron + atrazine at 20 + 1000 and 40 + 1000 g ha^-1 and a check without weed management. The crops management was the same from region. The spraying was done with CO₂ backpack pressurized equipment at 210 kPa, with four spray nozzles DG 11002, at 200 Lha^-1 of application volume. The evaluations were based on the efficacy of herbicides and production characteristics and weight of 100 grains. It may be concluded that using nicosulfuron associated to atrazine showed satisfactory control of Ipomoea triloba, Alternanthera tenella and Digitaria horizontalis. The major grains productivity of corn was obtained with the application of nicosulfuron + atrazine at 40 + 1000 g ha^-1. The weight of 100 grains was not affected by the weed community and herbicides treatments.