Controle de Digitaria insularis (L.) E Bidens pilosa utilizando diferentes formas de aplicação de calor

Abstract

One of the challenges that organic agriculture has been facing over the years is to develop efficient alternative techniques for the control of spontaneous plants, which in turn end up decreasing the production of cultivated plants, the value of the land and the quality of the product harvested in the Agriculture. The present work aimed to evaluate the control efficiency of spontaneous plants using three physical methods by heat induction: ceramic method, steam and flamethrower in plants of bitter grass (Digitaria insularis L.) and black bite (Bidens pilosa) at 32 days after the emergency. The experiment was conducted in a greenhouse at the Federal University of Fronteira Sul with 4 treatments and 10 repetitions. The variables analyzed were the percentage of physiological damage to the plants, the percentage of mortality and the percentage of sprouted plants. Treatment with flamethrowers resulted in a 20% mortality rate for B. pilosa, featuring a low control index. The steam resulted in a 60% mortality for D. insularis L. Although the preliminary results are unsatisfactory for its immediate use in agriculture, it demonstrates the potential of using the technique using heat in the future. For the improvement of alternative control techniques, future works should evaluate different equipment configurations in order to provide the adequate amount of heat for each species of spontaneous plant, exposure time and stage of development of greater susceptibility, for example.