Carryover and leaching of diuron + hexazinone + sulfometuron and mesotrione + atrazina and control of Mucuna aterrima

• Grant number: 13/13125-6
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2013
• Effective date (End): June 30, 2014
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal researcher: Patrícia Andrea Monquero
• Grantee: Érika Nascimento Braga
• Home Institution: Centro de Ciências Agrárias (CCA). Universidade Federal de São Carlos (UFSCAR). Araras , SP, Brazil

Abstract

This experiment will have the following objectives: (1) determine the leaching potential of mesotrione + atrazine, and diuron + sulfometuron + hexazinone herbicides through bioindicator and evaluate the effectiveness of these herbicides during this process in Mucuna aterrima control, and (2) evaluate the effect of these herbicides (carryover) in cultures of peanut, bean and cucumber at different times after application. In the first experiment, the treatments will be arranged in a factorial 2 x 2 x 2 with 2 amounts of straw (0, 10 t ha-1), two herbicides and two rainfall simulations (20 and 40 mm), for each species studied with four replications. Mesotrione + atrazine (0,25 + 3,0 L ai ha-1 ), and diuron + hexazinone + sulfometuron (1386 + 391 + 33.35 g i. ha-1) will be applied on top of soil columns with 0 and 10 t / ha of straw. Immediately after herbicide application, the tubes will be placed under precipitation with intensity of 1 mm min-1 during the time required to apply 20 and 40 mm precipitation. After this process, the columns will remain at rest for 72 hours. Columns (with straw and without straw) will be placed in a horizontal position and opened for sowing M. aterrima (target plant) and C. sativus (indicator plant). The second experiment will be conducted in a greenhouse, using vessels with a capacity of 10 L, filled with samples oxisol (clayey). The experimental design will be completely randomized with four replications. Saflufenacil (0.10 g ai ha-1) and diuron + hexazinone + sulfometuron (1386 + 391 + 33.35 g i. ha-1) will be applied. Crops of beans, soybeans, peanuts and cucumber are sown at different times after herbicide application (0, 7, 15, 30, 45 and 60 days). The phytotoxicity of herbicides will be determined at 7, 14 and 21 days after sowing (DAS) by means of a percentage score scale, where 0 corresponds to no injury to the plant e100 death of plants. In addition to the visual analysis, will also be determined to shoot dry biomass. (AU)