Eff ect of the herbicide sulfentrazone 50 SC, in two concentrations, alone and mixed with clomazone 36 CS, for controlling weeds in rice, Sébaco, rainy season, 2016

Abstract

An experiment was conducted in the dry season of 2016 at the Yerba Farm, located in the Sébaco Valley, La Majadita community, San Isidro, Matagalpa, Nicaragua. Six treatments were studied, two doses of Sulfentrazone 50 SC alone and two doses of Sultetrazone 50 SC in mixture with Clomazone 36 CS. One treatment was represented by the farmer`s management, and one treatment received no wedd control (absolute control). A design of Complete Blocks Randon (BCA) with four repetitions was used. The evaluated variables were density of weeds by types, total density, biomass by types, accumulated biomass, crop toxicity and grain yield. Analysis of variance and separation test were performed according to DMS at 5% error margin. The best behavior in the reduction of the density of weeds was obtained with the treatments Sulfentrazone, 0.28 1 ha-1 + Clomazone and Sulfentrazone 0.35 ha-1 + Clomazone, which showed greater effectiveness in the control of poaceae from seven days after the aplication, with 100% control, until 35 days after the aplication, with 99.91% control. The lowest accumulated biomass was presented by the Sulfentrazone 0.35 1 ha-1 + Clomazone treatment with 73.29% efficiency with respect to the absolute control treatments. The highest commercial yields were obtained by the treatment Sulfentrazone 0.35 1 ha -1 + Clomazone and Sulfentrazone 0.28 1 ha-1 + Clomazonem which represents an increase percentage of 62.43% and 62.32% in relation to the absolute control