Controle químico e cultural de Chamaesyce hirta em milho consorciado com Urochloa brizantha cv. Marandu e Crotalaria spectabilis

Abstract

The syndicated systems is an economically viable and sustainable management alternative that aims to intercropping of the main crop wih forages and/or other species for better use of the soil, with other benefits, such the weed control. The objective was to evaluate the cultural and chemical controle of Chamaesyce hirta in com single crops and intercropped with Urochloa brizantha cv. Marandu and Crotalaria spectabilis. The trial was conducted in the experimental area of the Center Mato Grosso College in Sorriso (MT). The design was a complete randomized block design, with split-plot and four replications. The plots consisted of six production system (single crops of maize, U. brizantha cv. Marandu and C. spectabilis and the intercropping among them) and three weed controls (weeded, unweayed and chemical control with atrazine). After the treatments were applied, a phytotoxification and control survey was conducted bringing up weed. At the maize harvest, the cover species green masses were collected and quantified, and measurements were made on 10 maize plants per plot for height, spike and plants per meter, and three maize lines of 2 meters in the harvested area of the plot to determine the production and yield components. The atrazine showed to be eficient in the control of C. hirta, selective to marandu palisadegrass and non selective to crotalária. There was a reduction of the dry matter mass of C. hirta. Maize yields were not affected in the intercropping.