Abstract
Ten plant species from the roads with heavy traffic in Abha Saudi Arabia were collected and studied for their phyto-monitoring potential by calculating their Air Pollution Tolerance Index (APTI). Physiological as well as the biochemical parameters like Relative Water Content (RWC), Ascorbate Content, leaf extract pH as well as the Total Chlorophyll Content (Chl) were used to calculate the APTI values. Bougainvillea glabra and Ricinus communis plants showed highest tolerance to vehicular pollution, Shinus molle, Catharanthus roseus, Hibiscus rosa-sinensis, Myoporum pieturn, Juniperus procera, Phoenix caespitora showed moderate tolerance while as Tagetestanui folia and Vitis vinefera were least tolerant species, thus making Bouganivillea glabra and Ricinus communis plants the ideal candidates to be used for green belt development in Abha region of Saudi Arabia.