Role of Poultry Manure and Corn Cob Biochar in Reducing Ozone-Induced Damage to Chili Plant (Capsicum annuum L.)

This study aims to assess the effect of tropospheric ozone (O₃) on chili (Capsicum annuum L.) yield and nutritional quality using two types of biochar (poultry manure, and corn cob) with 1% and 2% concentrations in the field. O₃ concentration ranged from 5 to 110 ppb, with an average of 43–59 ppb and AOT40 values exceeded by 6 ppm h over a 3-month period. Weekly assessments were carried out for plant height, leaf length, number of leaves, flowers, fruits, chlorophyll and elemental (Na, Fe, Mg, Mn), and enzymatic (Catalase, Flavonoids, Glutathione, Malon De aldehyde, Superoxide dismutase, Phosphoenolpyruvate, Phosphoenolpyruvate carboxylase) contents. Moisture, ash, protein and nitrogen analysis were conducted for leaves, roots, stems and fruits. Specifically, the number of leaves, leaf length, chlorophyll content, and number of fruits increased by 57%, 50%, 63% and 84.6%, respectively, for poultry manure 2%, followed by poultry manure 1%. Similarly, better elemental results were obtained for root, stem and leaves in the range of 10.3% to 60.2% for poultry manure 2% as compared to other treatments. Similar results were observed for moisture, ash, nitrogen and protein. Enzymatic analysis showed that the control group experienced significantly higher-level oxidative stress as compared to the treated group, however, this varied across different plant parts. The study concludes that tropospheric O₃ poses a threat to the quality and nutritional value of chili. However, biochar, especially poultry manure 2% effectively protects the plant from the detrimental effects of tropospheric O₃.