Air Pollution Tolerance Index (APTI) of Selected Tropical Ornamental Flowering Shrubs

Air pollution tolerance index of shrubs and the ability to remove volatile organic compounds were studied for using them as pollution indicators or for controlling pollution in the outdoor environment. Plants with high index value were tolerant to air pollution and vice-versa. On the basis of their indices, different plants were categorized into sensitive, intermediate, moderately tolerant, and tolerant classes. APTI values of 30 tropical ornamental flowering shrubs were estimated to find out their relative tolerance to air pollution. Shrubs like Calliandra haematocephala and Clerodendrum macrosiphon were tolerant and Hamelia patens and Pereskia bleo were sensitive to air pollution. Shrubs like Allamanda cathartica, Tabernaemontana coronaria and Pseuderanthemum reticulatum come under intermediate category and plants like Murraya exotica, Nerium indicum and Tecomaria capensis come under moderately tolerant category.