• Energy Research

The aim of this study was to investigate the impact of elevated concentration of carbon dioxide (CO2), as expected over coming decades, on yield and quality of winter bread wheat (Triticum aestivum L.). Plants (cv. Bologna) were grown by using the free-air CO2 enrichment (FACE) system at Fiorenzuola d’Arda under ambient (control) and elevated (570 ppm, e[CO2]) CO2 concentrations for two growing seasons. We addressed whether there would be a response of wheat grains to elevated CO2 concentration in terms of the contents of nitrogen (N), micro- and macronutrients, proteins and free amino acids. Under e[CO2], total wheat biomass and grain yield increased in both years of the study. Grain N percentage was reduced under e[CO2], but grain N yield (kg ha–1) was increased. Among macro- and micronutrients, a decrease in zinc concentration was observed. The proteome pattern was significantly different in grains grown at the two different CO2 levels, but the observed changes were highly dependent on interactions with prevailing environmental conditions. Finally, a negative trend was observed in the early germination rates of seeds from plants grown under e[CO2] compared with the controls. The results suggest that the expected increase in CO2 levels and their interactive effects with environmental variables may influence agronomic performance by increasing yield and negatively affecting quality.

Fusarium poae is one of the Fusarium species commonly detected in wheat kernels affected by Fusarium Head Blight. Fusarium poae produces a wide range of mycotoxins including nivalenol (NIV). The effect of temperature on colony growth and NIV production was investigated in vitro at 5-40 °C with 5 °C intervals. When the data were fit to a Beta equation (R2 ≥ 0.97), the optimal temperature was estimated to be 24.7 °C for colony growth and 27.5 °C for NIV production. The effects of temperature on infection incidence, fungal biomass, and NIV contamination were investigated by inoculating potted durum wheat plants at full anthesis; inoculated heads were kept at 10-40 °C with 5 °C intervals for 3 days and then at ambient temperature until ripening. Temperature significantly affected the incidence of floret infection and fungal biomass (as indicated by DNA amount) in the affected heads but did not affect NIV content in the head tissue. Inoculation of potted plants with F. poae did not reduce yield.