Evaluation of effects of simulated drift of glyphosate and sulfometuron-methyl on two reforestation tree species

• Grant number: 11/18370-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2012
• End date: December 31, 2012
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Pedro Luis da Costa Aguiar Alves
• Grantee: Marina Alves Gavassi
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Two important pioneer tree species used for the restoration of degraded gallery forest surrounding sugar cane plantations in São Paulo State will be studied in response to simulated drift of chemical maturation used for crop management. Two distinct experiments, each one for each species, will be carried out under semi-controlled conditions in order to evaluate some effects of drifting glyphosate (used as a plant maturation) or sulfometuron-methyl on Croton floribundus and Citharexylum myrianthum. Treatments will consist of the application of five doses of both chemicals (glyphosate at 9.6, 28.8, 57.6, 86.4 and 115.2 g ai ha-1 and sulfometuron-methyl at 0.75, 2.25, 4.50, 6.75 and 9.00 g ai ha-1), also maintaining no-treated plants as a treatment check. A completely randomized design will be set up with six replicates in each experiment. Before chemical application, leaf number, stem length, stem diameter, relative total chlorophyll content, chlorophyll fluorescence, and aboveground dry mass of both species will be characterized. These same determinations will also be performed at 7, 15, 30, 60, 90, and 120 days after application (DAA). At these same times, digital images will be recorded to monitor possible visual and morphological changes in plants resulting from chemical applications. In addition, photosynthesis rate, stomatal conductance, and transpiration rate will be performed at 30, 60, and 120 DAA. Data will be submitted to F test and Tukey test at 5% of probability. Concomitantly, data will be submitted to regression analysis, using the dose-response model.(AU)