Location: Plant Science ResearchTitle: Modeling the effects of tropospheric ozone on wheat growth and yield
|GUARIN, JOSE - University Of Florida|
|KASSIE, BELAY - Dupont Pioneer Hi-Bred|
|MASHAHEET, ALSAYED - North Carolina State University|
|ASSENG, SENTHOLD - University Of Florida|
Submitted to: European Journal of Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/5/2019
Publication Date: 2/5/2019
Citation: Guarin, J., Kassie, B., Mashaheet, A., Burkey, K.O., Asseng, S. 2019. Modeling the effects of tropospheric ozone on wheat growth and yield. European Journal of Agronomy. 105:13-23.
Interpretive Summary: Ground level ozone is formed by the action of sunlight on volatile hydrocarbons and nitrogen oxides produced during combustion of carbon based fuels. Although frequently considered an urban problem, ozone pollution is much broader in scope because weather systems transport the pollutants across long distances into agricultural areas. Ozone is toxic to plants, reducing the growth and yield of sensitive crops including wheat. Crop modelers at the University of Florida incorporated the effects of ozone into the DSSAT-NWheat crop model. The model reproduced the results from an ozone field trial conducted at Raleigh, NC by scientists from USDA-ARS and North Carolina State University. The modified NWheat model simulates the effects of ozone stress on wheat growth and yield and interactions with other growth factors and can be used to estimate impacts of climate change and air pollution on wheat production.
Technical Abstract: Elevated tropospheric ozone (O3) concentrations can negatively impact wheat growth by reducing photosynthesis and accelerating leaf senescence. Future global O3 concentrations are expected to increase in many regions, which will further limit global wheat production. However, few crop models consider the effects of O3 stress on wheat. We incorporated the effects of O3 stress on photosynthesis and leaf senescence into the DSSAT-NWheat crop model and reproduced an observed experiment and reported yield declines from the literature. Simulated wheat yields decreased as daily O3 concentrations increased above 25 ppb, with yield losses ranging from 0.26% to 0.95% per ppb O3 increase, depending on the cultivar O3 sensitivity. The model reproduced known wheat physiological responses from the combination of O3 stress with water deficit and elevated atmospheric CO2 concentration. Increased water deficit stress and elevated atmospheric CO2 both reduce the negative impact of O3, but yield benefits from elevated CO2 can be lost due to elevated O3 concentrations. The O3-modified NWheat model simulates the effects of O3 stress on wheat growth and yield in interaction with other growth factors and can be used for studies on climate change and O3 impacts.