Detecção e caracterização de populações de plantas com evidências de resistência ao herbicida glifosato em lavouras cafeeiras

• Autor(a) principal: Silva, Érika Cerqueira da
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/17208
• topic: Agronomia; Biotipos; Café; Resistência; subject.br-rjbn

Coffee exports are crucial for the economy of Espírito Santo. Since the introduction of Glyphosate, this herbicide has been applied repeatedly in the same area, a practice that has contributed to the selection of resistant weed biotypes. The objective of this work was to detect and characterize weeds suspected of resistance to glyphosate, which occur in coffee crops in the municipalities of Vargem Alta and Alegre, and to estimate the stomatal and physiological variables for resistance discrimination. For this, propagules of plants suspected of resistance were collected from coffee plantations in these regions. The experiment was carried out in a greenhouse at the Center for Agricultural Sciences and Engineering at the Federal University of Espírito Santo, in the municipality of Alegre. Six Digitaria insularis biotypes were evaluated in a completely randomized design with 5 replications, and the experimental plot consisted of vases of six biotypes with five herbicide applications. Stomatal variables were measured 14 days after herbicide application (DAA) and physiological variables were measured at 30 DAA. The B6 biotype was characterized as susceptible, presenting differences due to the higher stomatal density and greater stomatal conductance and for not resisting the glyphosate doses applied, presenting lower performances regarding the physiological indices of nitrogen balance, anthocyanin, flavonoids and chlorophyll. The other biotypes (B1, B2, B3, B4 and B5) were characterized as resistant, there were changes regarding the physiological indices of nitrogen, anthocyanin, flavonoids and chlorophyll balance, but the biotypes resisted the doses of glyphosate applied, confirming that the herbicide action did not reflect on control efficiency.