Leaf And Stem Anatomy Of Eleven Land Races Discorea Rotunda Of West Tropical Africa

ABSTRACT

The anatomy of leaf and stem of eleven land races of Discorea otiurcdatg was studied with the major aim of providing information that could be necessary in the intraspecific taxonomy of Di-corea rotiundata. Results from the investigation have proved that the leaf and stem anatomy exhibits such characters that could be included with other reliable attributes of this species in an attempt to fashion out an authentic classification scheme among the varieties of Discorea rotiundata. The presence of trichomes in the LE (Lower epidermis) of Aloshi and Makakwusa, the significant difference in stomata! frequencies and the straight anticlinal cells walls of Agbocha, Nwayieri and Dorban we. re major significant characters of the leaf epidermis seen. The nature of the stem; thickness of the stem cortex and number of vascular bundles and hairness of the stem are the features of the stem exploited in the systematic consideration of these Discoreg species varieties. The 10-12 layered cells of the cortex in Makakwusa, He-abalo separates them from other varieties studied. The vascular systems are arranged in a circular outline in all the land races investigated except in Dente which is triangular in shape which distinguishes it from other varieties. The relevance of all these observations on leaf and stem anatomy of ) 1 lan4 races of Discorea_rotiundata studied were discussed in details.