Soybean Plant Metabolism under Water Deficit and Xenobiotic and Antioxidant Agent Application
Julia Renata Schneider,
Mariele Müller,
Vilson Antonio Klein,
Luciana Grazziotin Rossato-Grando,
Rômulo Pillon Barcelos,
Genei Antonio Dalmago,
Geraldo Chavarria
Affiliations
Julia Renata Schneider
Plant Physiology Laboratory, Agronomy Post-Graduate Program, Faculty of Agronomy and Veterinary Medicine, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
Mariele Müller
Plant Physiology Laboratory, Agronomy Post-Graduate Program, Faculty of Agronomy and Veterinary Medicine, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
Vilson Antonio Klein
Soil Physics Laboratory, Agronomy Post-Graduate Programa, Faculty of Agronomy and Veterinary Medicine, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
Luciana Grazziotin Rossato-Grando
Faculty of Pharmacy, Institute of Biological Sciences, Bioexperimentation Post-Graduate Program, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
Rômulo Pillon Barcelos
Faculty of Pharmacy, Institute of Biological Sciences, Bioexperimentation Post-Graduate Program, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
Genei Antonio Dalmago
Sustainable Production Systems, Ecophysiology, Embrapa Wheat, Rodovia BR 285, Km 294, Passo Fundo 99050-970, Rio Grande do Sul, Brazil
Geraldo Chavarria
Plant Physiology Laboratory, Agronomy Post-Graduate Program, Faculty of Agronomy and Veterinary Medicine, Passo Fundo University, BR 285, Passo Fundo 99052-900, Rio Grande do Sul, Brazil
The aim was to evaluate the interactive effects on biochemistry and physiology of soybean plants exposed to simultaneous xenobiotic and water deficit stresses, and the possible attenuation of plant damage by an antioxidant agent. Soybean plants were submitted to eight different soil water potentials, in two experiments (first experiment: −0.96, −0.38, −0.07, −0.02 MPa, and second experiment: −3.09, −1.38, −0.69, −0.14 MPa), xenobiotic, and antioxidant agent applications. Was observed a reduction in water status, gas exchange, photosynthetic pigments, photosystem II quantum yield, and increased leaf temperature in plants under low water availability. Water deficit also induced oxidative stress by the increased production of reactive oxygen species, cellular and molecular damage, and induction of the antioxidant defense metabolism, reduction of gas exchange, water status, and photosynthetic efficiency. The xenobiotic application also caused changes, with deleterious effects more pronounced in low soil water availability, mainly the reactive oxygen species production, consequently the antioxidant activity, and the oxidative damages. This indicates different responses to the combination of stresses. Antioxidant enzyme activity was reduced by the application of the antioxidant agent. Principal Component Analysis showed a relation with the antioxidant agent and reactive oxygen species, which is probably due to signaling function, and with defense antioxidant system, mainly glutathione, represented by thiols.
