Seletividade de herbicidas pré-emegentes em cultivares de batata-doce (Ipomoea b(L.) Lam.), desenvolvidas para produção de etanol

Abstract

The present studies aimed to evaluate the effects of pre-emergent herbicides applied in the sweet potato. The experiment was conducted at the experimental area of the Energy Systems of Production Laboratory (or Laboratory of Energy Systems of Production), from the Renewable Sources of Federal University of Tocantins (UFT), campus of Palmas. An experiment was built in the field. The Delineating utilized was in Caused Blocks (DBC), in scheme factorial 3 x 2 + 1, following the factor 1: the cultivars (Amanda, Carolina Vitória and Brazlândia Roxa) and the factor 2: the herbicides (S-metolachlor) and (Atrazine + Smetolachlor) and with witness (without application of herbicides), with four repetitions. The averages of the treatments were submitted to analysis of variance and, after, they were compared by the Tukey test to 5% of probability. It was realized analysis of Dry Matter of root tuberous, toxicity, the dry biomass of the aerial part (shoot biomass), productivity, the content of starch of the tuberous root and estimate of productivity of ethanol. It was observed that herbicides S-metolachlor and Atrazine + S-metolachlor caused a reduction in the varieties of productivity and estimate in the rate of ethanol, mostly in the Carolina Vitoria and Brazlândia Roxa’s cultivares in regarding to the witness. As the content of starch, dry substance of root tuberous and dry biomass of the aerial part was not observed any difference in regarding to witness. However in regarding to the variable toxicity, there was one significant difference in regarding to the witness. With these outcomes it can be notice that the pre-emergent herbicides that was studied in this work, they have selective potential to sweet potatoes, however they need more studies in regarding their selectivity.