Thermotolerant wheat cultivar (Triticum aestivum L. var. WR544) response to ozone, EDU, and particulate matter interactive exposure.

The present study was conducted to assess the response of thermotolerant wheat cultivar (Triticum aestivum L. var. WR544) to individual and combination of ambient ground level ozone (AO3) and particulate matter (PM) air pollutants with ethylene diurea (EDU) used as an ozone stress mitigator. The four treatment combinations to which wheat cultivars were exposed are T1 (AO3 + PM), T2 (EDU + PM), T3 (AO3-PM), and T4 (EDU-PM). The effect of different treatments on morphological (foliar ozone injury, leaf area, shoot height, number of leaves, and total biomass), biochemical (leaf extract pH, electrical conductivity, relative water content, total chlorophyll, ascorbic acid content), nutritional (leaf carbohydrate content and leaf protein content), and yield (biological yield, economic yield, and harvest index) attributes of the cultivar were monitored. The plants under T1 experienced 20-30% foliar ozone injury and recorded lowest economic yield (0.58 g/plant). Plants under T2 and T3 showed visible foliar ozone injury range between 0 and 5% whereas plants under T4 exhibited negligible ozone injuries. EDU-treated plants without PM deposition (T4) exhibited better morphology, leaf protein content, leaf carbohydrate content, biological and economic yield as compared to T1-, T2-, and T3-treated plants but EDU was only partially effective. Despite being a thermotolerant variety, WR544 gets adversely affected by the individual and combined exposure of AO3 and PM air pollutants. These result findings highlighted the need for more detailed study of air quality impact on the thermotolerant cultivars of other key crops to individual and combined air pollutants.