The response of antioxidative defence system of spring barley (Hordeum vulgare L.) and barnyard grass (Echinochloa crus-galli L) under elevated CO2 and temperature

Abstract

The major components of climate change include warmer temperature and elevated atmospheric carbon dioxide (CO2) concentrations. Agricultural yields strongly depend on crop competitiveness with weeds. Climate change will have obvious consequences for crop yields as any differential response between crops and weeds to changing climate will alter weed-crop interaction and potential crop yield losses. As C3 and C4 plant species respond differently both to rising CO2 and rising temperature, this may alter crops ability to compete with C4 weeds. The aim of this study was to investigate the response of antioxidative defence system of spring barley (Hordeum vulgare L.) and barnyard grass (Echinochloa crus-galli L.) under future climate conditions. Two climate scenarios were investigated: current climate (21 °C, 400 ppm CO2) and future climate (25 °C, 800 ppm CO2). The plants were grown in microcosms: spring barley in competition with barnyard grass. The growth and response of antioxidative defence system were evaluated. Antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were measured. Oxidative stress parameters, such as the concentrations of malondialdehyde were determined. Our results indicated that spring barley and barnyard grass responded in different manner to future climate conditions. It was observed that barnyard grass could become more competitive with barley under future climate conditions.