Taxonomic Significance of Foliar Epidermal Characters in <i>Azanza garckaena</i> (<i>F. Hoffm.</i>) Exell & Hillc in Tula, Kaltungo Local Government Area of Gombe State, Nigeria

Abstract

Leaf epidermal microscopy of <i> Azanza garckeana </i> was studied in search of stable taxonomic characters and delimitation of the plant. Fresh leaves were obtained from 3 accessions in Tula: Tula Wange, Tula Baule and Tula Yiri/Bwaile respectively. Leaf epidermal peels of both surfaces of the plant were made using free hand sectioning and maceration methods. Temporary slides were prepared for observations under light microscope to examine their stomatal features, epidermal cell shapes, and anticlinal cell-wall patterns. The result revealed epiamphistomatic leaves, Stomatal complex type (SCT) was exclusively anomocytic, epidermal cell shape s w ere all irregular in shape, with curved anticlinal cell wall patterns. There was no significant difference on the abaxial surface across all the parameters at all accessions but significant difference exists (P ≤ 0.05) on some characters on the adaxial surfaces. The Stomatal density was the highest on the adaxial surface of accession I (23.67 ± 4.04a) and the lowest on the adaxial surface of accession II (13.33 ± 2.08 ^b mm 2 ). The Stomatal sizes of abaxial surface of accession I was the highest (45.49 ± 3.73 μm), while adaxial surface of accession III showed the lowest (24.98 ± 2.27a μm). The Stomatal index was the highest (7.42 ± 2.30a) on the adaxial surface of accession I, and the lowest ( 4.23 ± 0.20b ) on the abaxial surface of accession II. It was concluded that there were similarity of anomocytic type of stomata, small and large stomatal sizes, presence of dendritic tric homes, irregular and curved epidermal cells on both leaf surfaces , and variations in the stomatal index within all the accessions. Although these variations are good and reliable taxonomic features of the accessions. More taxonomic tools are required for the delimitation of the accessions into distinct taxa.