This project aims to evaluate the impact of increasing tropospheric ozone pollution on changes in antioxidant and glucosinolate (natural toxin) composition of Brassica species. These are important factors in relation to health and safety aspects of the food and feed chain.
1. to determine the impact of increasing tropospheric ozone concentrations on antioxidant and glucosinolate composition of Brassica species.
2. evaluation of the influence of ozone on the human diet and animal feed intake by incorporating the changes in antioxidant and glucosinolate levels in the food chain
3. to identify physiological and biochemical biomarkers for ozone stress by investigating the interaction between stress induction and changes in secondary metabolites.
4. elucidation of interaction between abiotic stress induction, defence pathways and changes in secondary metabolites by means of transcriptoom analysis
5. evaluation of impact of ozone induced changes in glucosinolate content and composition in relation to plant-pathogen/insect interaction through literature study
6. to determine yield losses and changes in yield quality
7. to contribute to ozone flux modelling by providing data on environmental dependence of stomatal conductance of oilseed rape and broccoli.
To achieve the main objective, oilseed rape or canola (Brassica napus L.) and broccoli (Brassica oleracea L. cv. Italica) will be exposed to different levels of ambient ozone concentrations during their entire growth. The experiments will be performed under «near-field» conditons in 15 Open-Top Chambers (OTCs) at the Veterinary and Agrochemical Research Center (VAR) in Tervuren and be repeated over 3 consecutive years to ensure sufficient environmental variation for data extrapolation. Comparison with unframed «open¿field» plots enables determination of the variation in ozone flux at the leaf level under fluctuating climatic conditions (soil moisture, air humidity, temperature, global radiation).
The Research Group of Plant and Vegetation Ecology of the University of Antwerp is responsible for the physiological assessments of plant heath throughout the experiments. This will be achieved through measurements of gas exchange and chlorophyll fluorescence at the leaf level. The main objective of these measurements is to identify the extent to which O3 fumigation is causing a physiological stress response in the plants and to relate these events to changes in biochemical profiles.