Comparative Anatomical and Micromorphological Studies on Some Species of Lathyrus L. Section Lathyrus (Papilionoideae, Fabaceae)

Lathyrus L. (Papilionoideae, Fabaceae) is considered economically, ecologically, and genetically among the most significant genera of the flowering plants having its centre of diversity in Southwest Asia where Turkey is located. The anatomical and micromorphological characteristics of species of the genus Lathyrus have been reported in only a few studies. Thus, in the present study, comparative anatomy and leaf epidermal micromorphology of L. cassius Boiss., L. chloranthus Boiss. & Balansa, L. cicera L., L. hirsutus L., and L. sativus L. belonging to the section Lathyrus of this genus are comprehensively investigated by light and scanning electron microscopy so as to assess the taxonomic importance of anatomical and micromorphological characters in species separation. The results obtained reveal that some anatomical and micromorphological characters have proved useful for discrimination at the species level. Anatomical and micromorphological properties of taxonomic significance are as follows: the number of ray rows in the root, the outline of the stem in transverse section, the ratio of the wing length to the stem diameter, the number of vascular bundles in each wing, the shape of leaf epidermal cells, the pattern of their anticlinal walls, and the presence/absence of trichomes on the leaf.