Rising Tropospheric Ozone Impacts on Pathogen Resistant Pepper (Capsicum annuum)

Abstract

The increase of anthropogenic emissions has led to rising of global surface temperatures, as well as increases in secondary greenhouse gas pollutants. A particularly dangerous secondary pollutant is tropospheric ozone, which has been identified as the third-most potent greenhouse gas following carbon dioxide and methane. Ozone is formed by the photochemical oxidation of primary pollutants such as nitrogen oxides, methane, carbon monoxide, and volatile organic compounds by ultraviolet (UV) sunlight in the troposphere. The accumulation of ozone has risen with the industrial revolution, rising the average concentration from 10 parts per billion (ppb) in the 1800s to 40-50 ppb by the 2010s. This daily maximum concentration fluctuates globally, depending on factors such as population density, urban development, and intensity of UV radiation. Increasing concerns over the effects of global climate change has led to research dedicated to direct impacts on overall plant health, as well as the secondary impacts on plant mechanisms controlling other environmental response pathways. The aim of this thesis research is to understand the physiological and transcriptomic impacts elevated ozone will have on plant-host interactions. Specifically, how disease-resistant cultivars may be affected by combined stress treatments.