Presentation of Plugged Stomatal Pores in the Leaf of Sida acuta

Background and Objective: This study aimed at the determination of the effects of air pollutants on the leaves of Sida acuta, an erect perennial weed shrub of cultivated crops, pastures, roadsides and waste areas that is widespread in West Africa. Methods: Matured leaves of Sida acuta were collected from the sides of three busy roads and from the forest areas of three remote villages thus constituting the polluted and non-polluted populations respectively. Results: The polluted and non-polluted populations had average Leaf Areas (cm 2 ) of 7.79 ± 0.44 and 9.93 ± 0.17 respectively. The leaves of the two populations were amphistomatic and contained anisocytic stomatal in the upper epidermis while the lower epidermis of both leaf populations contained a combination of anisocytic and anomocytic stomatal types. The stomatal pores in leaves of the polluted populations were plugged thus preventing data collections on them. The leaves of the non-polluted populations were opened with average mean lengths and widths (µm) of 1.05 ± 0.39, 1.14 ± 0.44, 1.02 ± 0.31 and 0.21 ± 0.14, 0.18 ± 0.27, 0.33 ± 0.13 for the upper epidermis of the non-polluted populations respectively. Also, they had 1.01 ± 0.91, 1.16 ± 0.83, 1.99 ± 0.20 (pore mean length) and 0.95 ± 0.12, 0.44 ± 0.60, 0.89 ± 0.15 (pore mean width) on the lower epidermis respectively. The epidermal leaf surface architectures were represented in line drawings for illustrations. Alterations such as plugged stomatal pores, ruptured stomatal ledges, reduced Leaf Area (LA) and perforations of epidermal leaf surfaces were observed in the polluted leaves of the polluted populations. Conversely, these forms of alterations were not observed on the leaves of the non-polluted populations. Conclusion: The alterations observed in samples collected from polluted area were the aftermaths of the various traffic air pollutants that the leaves were exposed to by the sides of the busy roads. It was concluded that Sida acuta should be noted as alternative plant that can serve as an indicator of vehicular air pollution of the environment.