Comparative Microscopic Analysis of Leaf Petiole Anatomy in Ten Leguminous Species from Central Sudan

Background and Objective: Petiole anatomy plays a crucial role in plant taxonomy, yet limited data exists on its significance in leguminous species. This study investigates the anatomical structure of petioles in ten leguminous species from Central Sudan, spanning the sub-families Caesalpinioideae, Faboideae and Mimosoideae to explore and assess the utility of petiole anatomical features in the taxonomy of selected leguminous species, providing insights into species-level classification. Materials and Methods: Transverse sections of petioles from ten leguminous species (Caesalpinia pulcherrima, Cassia italica, Cassia obtusifolia, Cassia siamea, Cassia sieberiana, Tephrosia apollinea,Vigna unguiculata, Crotalaria saltiana, Cajanus cajan and Leucaena leucocephala) were examined using light microscopy. The anatomical features, including epidermal cell shape, hypodermal layers, vascular bundle arrangement and trichome types, were analyzed. A common significant level used in biological studies is p<0.05. Results: The six distinct petiole anatomical patterns were identified across the species. Differences were noted in epidermal cell shapes, hypodermal layer structures, vascular bundle arrangements and trichome types. Two main anatomical patterns emerged: One characterized by a small pith and abundant sclerenchyma and another with a large pith and limited sclerenchyma. Conclusion: Petiole anatomy provides valuable insights for species-level taxonomy and the definition of smaller natural groups within leguminous species. However, it is less effective for broader taxonomic classifications.