Air pollution is one of the major problems in the Delhi NCR region due to industrial emissions, traffic congestion, population growth and rapid development. Air pollutants deteriorate the environment, human health, plants and crops. This study focuses on the physiological parameters and yield attributes of paddy and wheat crops in the vicinity of a gas-based national thermal power plant (NTPC) located in Faridabad. Ten sites were selected, including the control site within a 10 km aerial distance from the exhaust chimney stack of the power plant. Major air pollutants, such as NOx, SOx, O3, and PM10, were monitored using Central Pollution Control Board (CPCB) guidelines. The air quality index (AQI) was moderately polluted at the sampling site, while good air quality was observed at the control site. The results showed that the photosynthetic rates were reduced to 46% in paddies and 48% in wheat crops. In the vegetative growth stage of paddies and wheat crops, the stomatal conductance of paddies decreased to 0.11 mmol m-2s-1 compared to 0.19 mmol m-2s-1 at the control site. The transpiration rate ranged from 0.6 to 7.7 μmol/m2/s in paddies and 1.2 to 9.8 μmol/m2/s in wheat crops. The R2 value ranged from 0.702 to 0.985, which shows a strong impact of the air quality index on the physiological parameters of crops. The yield reduction due to air pollution in paddies was 11.6%, and in wheat crops, it was 14.8%. This study also provides an inventory of air pollutants in Faridabad region and their subsequent impacts on crops
