The response of antioxidative defence system of Spring Barley (Hordeum Vulgare L.) and Wild Mustard ( Sinapsis Arvensis 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. Changing climate will alter weed-crop interaction and potential crop yield losses. The objective of this study was to investigate the response of antioxidative defence system of spring barley (Hordeum vulgare L.) and wild mustard (Sinapsis arvensis L.) under future climate conditions. The growth of spring barley was evaluated with and without the presence of wild mustard at ambient (21 oC, 400 ppm) and elevated (25 oC, 800 ppm) temperature and CO2. The growth and response of antioxidative defence system were evaluated. Antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) were measured. Oxidative stress parameters, such as the concentrations of malondialdehyde were determined. The growth of both spring barley and wild mustard grown in monoculture was increased under raised temperature and the CO2 concentration. In contrast, the growth performance of spring barley under competitiveness conditions with wild mustard was decreased in both ambient (21 °C, 400 ppm CO2) and future climate (25 °C, 800 ppm CO2). The activity of the antioxidants (CAT and SOD) in the monoculture spring barley tissues was decreased significantly (p<0,05) under elevated temperature and CO2 conditions in comparison with current climate. While, antioxidative enzymes activity in spring barley grown in mixture with wild mustard responded to elevated climate in different manner: CAT activity was significantly (p<0,05) decreased by 45 %, while SOD activity showed statistically significant (p<0.05) increase by 71 % in comparison with monoculture. The results of this investigation suggest that competitiveness ability of agriculture plants such as spring barley may decrease in a warming climate.