Light Microscope Study of the Stems and Petioles of Some Species of Cissus in Nigeria

  • J. E. Otoide
  • P. O. Tedela


The internal features in the stems and leaf petioles of Cissus quadrangularis, C. arguta, C. glaucophylla, C. aralioides and C. rufescens have been studied with the aid of light microscope. Transverse sections of the stems and petioles were prepared into slides following standard procedures. Observations of the slides through the microscope revealed internal features of diagnostic significance in all the Cissus species. Features such as outline of stem and petiole epidermis, leaf trace bundles, orientation and number of units of vascular bundles and occurrences of starch grains and raphids where part of the key internal morphological features observed in the species. These internal features were not uniform in their occurrences in the five species as there were instances where some of the features were not found. Consequently, the epidermis of stem of C. arguta and C. quadrangularis developed six and four loops respectively. These loops gave them characteristic undulating epidermal outline that distinguished them from the rest of the Cissus species examined. Each of the loops showed localized collenchymal cells. Furthermore, the occurrences of leaf trace bundles in the stem of C. glaucophylla and C. aralioides is diagnostic as they were absent in the rest of the species. Raphids were observed in the stem and petiole of C. quadrangularis but present only in the leaf petiole of C. arguta. In all, only the stem of C. aralioides revealed deposits of starch grains in most of the cortical cells. Radial bundles arranged in ring-like pattern were observed in both the stem and leaf petioles of the Cissus species. It was asserted that the internal features observed were diagnostic, descriptive, useful and reliable in the identification of the species when they appear in sterile or shriveled forms and also supported the present taxonomic status of the species as separate individuals belonging to the same genus. It was stressed that the internal features of the stems and petioles of C. arguta, C. glaucophylla, C. aralioides, C. quadrangularis (petiole) and C. rufescens are being reported for the first time as there exist no or little information about their anatomy.Key words: Cissus, stem, petiole, internal features, diagnostic