Leaf Epidermal Analysis of Five Species of Asteraceae

The leaf epidermal features of five species within the family Asteraceae, namely Aspilia africana, Ageratum conyzides, Emilia sonchifolia, Tridax procumbens, and Vernonia cinerea were investigated using the traditional peeling technique where fresh and matured leaves were collected, washed in tap water and immersed in a bowl of water to facilitate peeling. Peeling was done with a sharp razor blade. The peeled surfaces were soaked in Bleach and then stained with safranin for 10mins and washed with water before mounting on slides for microscopic observation. Results show that stomata are anomocytic and amphistomatic in all species. At the upper surface, stomatal frequency was 43-46 in A. africana, 31-75 in E. sonchifolia. Stomatal index was highest in T. procumbens (30.95%) but least in A. africana (13.30 %). Two types of trichomes were recorded. That is glandular and non glandular trichomes. On the lower surface, there epidermal cell wall ranged from hexagonal to polygonal in E. sonchifolia but irregular in other four specie. E. sonchifolia (19) has the least number of stomatal frequency while A. africana(67) has the most stomatal frequency. The differences in the stomatal frequency can be a delineating factor among the five species. The results of this study have shown some similarities between the five species studied, showing resemblances and reasons for them to be in the same family. Detailed studies are needed to ascertain the true taxonomic and phylogenetic values of epidermal features in the family Asteraceae.