Plants as bioindicators based on air pollution tolerance index

In the present study 30 Plants i.e. 10-Trees, 12-Shrubs and 8-Herbs growing in various places of Hyderabad city were selected and analysed for certain physiological and bio-chemical parameters, pH of the leaf extract, Leaf Relative Water Content, Ascorbic acid content and Total chlorophyll content. Based on these parameters APTI (Air Pollution Tolerance Index) values were calculated. Plants absorb the air pollutants and they act as natural-sinks, depending on the APTI values the plants are categorized into “Tolerant” species and “Sensitive” species. According to the present study Azardirachta indica, Peltaforum alba and Cassia species among the trees; Annona squamosa, Ocimum sanctum and Hibiscus rosasinensis among the shrubs; Tridax procumbence, Portula species and Croton species among the herbs- are the “Tolerant” species. These tolerant plants can be used as bioindicators to monitor the health of the environment. The tolerant plants can also be used by the landscapers for planting them on either side of roads, parks, dividers etc.