Avoidance Mechanism in Plants Against Automobile Exhaust Pollution

The effect of automobile exhaust pollution was investigated on stomatal behaviour of four wild dicotyledonous plants growing along road with heavy traffic. These plants responded to automobile exhaust pollution by showing either complete or partial closure of stomatal opening resulting in more stomatal resistance to restrict the pollutants. Of the different plants studied, viz., Cassia sophera, Glycosmis penta-phyila, Calotropis procera, and Mikania scandens. Cassia sophera was found to be the most efficient and Calotropis procera, the least efficient in avoiding pollution effects.