Avaliação da eficiência de 2,4-D + Picloram na dose recomendada em diferentes alturas de corte de Sida cordifolia L

Abstract

The Sida genus has a wide scope in Brazil and in the world, being widespread in the Northeast of Brazil, produced by the production of crops due to its intense intensity of water, light and nutrients, as well as the difficulty of management. The present work aimed to evaluate the efficiency of 2,4-D + Picloram in the recommended dose at different cutting heights of Sida cordifolia L. The experiment was conducted in the experimental area of the Biology and Weed Management Sector of the Engineering and Science Campus Agrarian - CECA, Federal University of Alagoas, Rio Largo, AL. The experiment was installed in a completely randomized design in a 5x6 factorial scheme, with 6 treatments and 5 replications. The experimental plots consisted of receivers with a capacity of 20 kg. The experiment consisted of cuts at the top of 20 cm, 40 cm, 60 cm, 80 cm and without cuts, starting from the soil line, associated with the herbicide 2,4-D + Picloram in the recommended dose plus the control without cuts and without herbicide. As biometric comments from the initial growth phase until the day of the cut consisted of plant height, stem diameter, number of leaves. After the cuts, the total dry matter weight was measured and after applying the herbicide, visual scales for phytotoxicity were made. At the time of the cut as plants, they were on average 1 meter high, 50 leaves per plant and 9.4 mm in stem diameter. It was observed that the plants that received the herbicide had similar weight, ranging from 7.9 g to 9.4 g. The uncut and herbicide control had the greatest weight as among others. Using the scale of notes, found that at twelve days after application there was total death of the plants regardless of the height of the plants. The herbicide 2.4-D + Picloram when applied in the dose, promoted efficient control in all heights of cuts studied of Sida cordifolia L. in 12 days after application.