Impact of Elevated Ozone on Cabbage

Abstract

Tropospheric ozone (O3) is a pervasive greenhouse gas and air pollutant known for its detrimental effects on human health and vegetation. In the recent years, tropospheric ozone has been rising steadily on the account of rapid urbanization and globalization. Hence, a study to investigate the impact of elevated ozone levels on cabbage cultivars have been initiated. The cultivars Tekila and Primero, which are extensively grown in the high-altitude region of the Western Ghats, India were used as test crop, where ozone levels are a growing concern. The study employed a comprehensive experimental design, encompassing ozone stress (200 ppb), cabbage varieties (Tekila and Primero), and different growth stages of the cabbage plants. Ozone fumigation at 200 ppb was used to simulate elevated ozone conditions, reflecting potential future scenarios. To assess the extent of impact both physiological and biochemical parameters were extensively analyzed. The results revealed that elevated ozone concentrations had a significant negative impact on both cabbage cultivars. Photosynthetic rate, stomatal conductance, and chlorophyll content declined progressively as ozone exposure continued, leading to maximum reductions of 71.2, 81.03 and 32.98% respectively. However, protective mechanisms were activated in response to ozone stress, including increased proline by 32.24%, ascorbic acid by 64.75%, catalase by 3.58%, and peroxidase activities by 56%, suggesting the cabbage plants' efforts to mitigate oxidative damage. Overall, this study highlights the vulnerability of cabbage cultivars to elevated ozone levels and emphasizes the need for effective mitigation strategies to safeguard crop productivity and ensure sustainable agriculture in regions facing escalating ozone pollution. Further research is essential to develop and implement solutions that can protect vital crops like cabbage from the adverse effects of tropospheric ozone.