Basant Shubhankar, Nityananda Shaw, Rajesh Kumar, Neeta Sinha, Swati Vats and Suchitra Tyagi
Abstract
Air pollution presents a significant threat to crop productivity and food security, particularly in industrial regions. This study evaluates the biochemical responses and air pollution tolerance of Oryza sativa (rice) cultivated across five villages surrounding the Tata Steel Plant in Jamshedpur, Jharkhand, during the 2023 and 2024 growing seasons (May-July). The objective was to assess the impact of ambient industrial pollution on rice by measuring key biochemical parameters - leaf extract pH, relative water content (RWC), ascorbic acid (AA), and total chlorophyll - and to compute the Air Pollution Tolerance Index (APTI) at three developmental stages: vegetative, reproductive, and maturity. Air Quality Index (AQI) data indicated moderate to poor air quality at locations closer to the industrial zone, with Bada Govindpur (the control site) exhibiting the cleanest air. Biochemical analyses revealed site-specific variations influenced by pollution levels. Leaf pH and RWC decreased significantly under elevated AQI, whereas AA levels increased, indicating oxidative stress response. Chlorophyll content declined under polluted conditions, reflecting impaired photosynthesis. APTI values ranged from 10.35 to 13.36, with the lowest at Ghorabanda and the highest at Bada Govindpur. Rice yield showed considerable variation, ranging from 220 - 258 kg/acre in 2023 and 223 -260 kg/acre in 2024. The highest yield loss (~14.7%) was observed in high-pollution sites, while minimal losses occurred where APTI values and biochemical stability were higher. Correlation analysis revealed strong positive associations between APTI, RWC, pH, and chlorophyll, while AA showed an inverse correlation. Linear regression analysis demonstrated that AQI significantly explained variations in RWC (R² = 0.89 - 0.94) and AA (R² = 0.78â0.92). These findings confirm APTI as a robust integrative metric for assessing crop resilience to air pollution stress. Biochemical markers such as RWC, pH, and AA serve as early indicators of pollutant-induced stress and can inform adaptive, pollution-resilient agricultural strategies in industrially impacted regions.