Air pollution tolerance index of Persea bombycina: Primary food plant of endemic muga silkworm (Antheraea assamensis)

Air pollution poses a significant threat to human health, ecosystems, and the livelihood of tribal communities. This study focuses on understanding the impact of air pollution on the primary food plant som (Persea bombycina Kost.) of the endemic Muga silkworm (Antheraea assamensis) and its implications for muga silk production. The study was conducted at two sites in northeastern India, one free from atmospheric pollutants (FAP) and the other affected by pollution from an oil refinery (PAS). Various atmospheric pollutants, including particulate matter, hydrocarbons, and heavy metals, were found to be higher at the PAS site. The study investigated biochemical parameters like ascorbic acid, relative water content, total chlorophyll, and extractable pH in the leaves of P. bombycina to determine its air pollution tolerance index (APTI). Results showed that the ascorbic acid content in the leaves increased significantly at the PAS site (p < 0.05), indicating the plant's adaptation to air pollution stress. Similarly, the APTI values were higher during summer compared to winter, suggesting better tolerance during the former season. Positive correlations were found between APTI and ascorbic acid content (p < 0.05), emphasizing the role of ascorbic acid as an antioxidant in mitigating the effects of air pollution. The study highlights the importance of understanding the tolerance levels of P. bombycina to develop protective measures for sustaining Muga silk production in the face of rapid industrialization and increasing pollution. This research can aid policymakers in balancing economic growth with environmental conservation and protecting traditional practices of tribal communities.