Anatomical study on Commelina diffusa burn F. and Commelina erecta L. (Commelinaceae)
Commelina diffusa Burn. f. and Commelina erecta L. (Commelinaceae) are known from tropical and subtropical regions of the world. In the present work, the leaf epidermal characters, midrib and stem anatomy were studied in relation to their taxonomic values. Voucher specimens collected from different parts of Abia, Rivers, Bayelsa and Delta States were analysed. The samples were fixed in FAA, dehydrated in series of ethanol (50%, 70% and 90%), peeled/sectioned, stained in 2% aqueous solution of Safranin O, counter stained in Alcian blue for about 3- 5 minutes, mounted in glycerine, viewed and micro-photographed using Leica WILD MPS 52 microscope camera on Leitz Diaplan microscope. Comparative foliar epidermal features, midrib and stem anatomical characters of the two Commelina species indicated that the leaf epidermal characters showed close similarity among the species though with few distinguishing features while the anatomical features of the midrib and lamina could be used to distinguish these species.
Keywords: Commelina, Epidermal features, midrib anatomy, leaf lamina