Comparative Anatomical Characteristics of Emergent Aquatic Herbs-Monochoria vaginalis (Burm. F.) Presl. and Monochoria hastata Solms. (Pontederiaceae)
by Narayanan K. B., Kaliappan I. (2014)
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in International Journal of Botany 10 (1): 13-23 – DOI: 10.3923/ijb.2014.13.23
https://scialert.net/fulltextmobile/?doi=ijb.2014.13.23
Abstract
The present investigation explores and compares the detailed anatomical features of an emergent aquatic herb of Monochoria vaginalis and Monochoria hastata, belonging to water-hyacinth family, Pontederiaceae. These weedy plants are claimed to be highly nutritious and medicinally valuable among many ethnic communities throughout India. But due to their morphological similarity among the related species of this family, identification and utilization of the plant has been ignored and urbanization has resulted in eradication of the herb on the basis of environmental wet land pollution issues.
Both species exhibits unique hydromorphic anatomical features related to the adaptability of the plant to the aquatic environment. Though both species share most of the anatomical features in common, few differences observed in the leaf anatomy like dorsiventral lamina, brachy-paratetracytic stomata of M. vaginalis and isobilateral lamina and paracytic or cytocytic stomata of M. hastata will provide valuable information for the plant identification.
Even though both the species share common morphological features in common which make them difficult to identify, the microscopical variations observed from the current report helps in identification and will meet the demand of standardization requirements of medicinal herbs.
Epidermal cells and stomata
Monochoria vaginalis: Para dermal sections were used for studying the stomatal type and epidermal cells. The stomata are present on both upper and lower sides of the lamina. The stomata are brachy-paratetracytic type (Fig. 2d). A stoma has two lateral subsidiary cells and two larger polar subsidiary cells situated on the upper and lower poles of the guard cells. The guard cells are oblong, elliptic measuring 20×50 μm in size. The epidermal cells are fairly thick walled, angular and compact (Fig. 2e).
Monochoria hastata: Stomata occur on both the upper and lower surfaces of the lamina. They are diffused and random in distribution. The stomata are either paracytic or cytocytic, the former being more in frequency (Fig. 2j), the paracytic stoma has two wing like subsidiary cells, one on either side of the guard cells and parallel to the guard cells (Fig. 2k). In the cytocytic type, a stoma is surrounded by four subsidiary cells, two cells being polar and other two being lateral in position.
