Foliar epidermal and trichome micromorphological diversity among poisonous plants and their taxonomic significance

Abstract

Scanning microscopic imaging has become a valuable research tool in micromorphology with improved techniques playing an important role in analysing the ultrastructure of leaf specimens. The foliar epidermal anatomy of 25 selected poisonous plants with special emphasis on stomata and trichomes was reported using microscopic techniques, for instance, light micrographs (LMs) and scanning micrographs (SEMs). This study aimed to investigate micromorphologies of studied species that are helpful for the identification of poisonous plants. Plants were collected, pressed, dried, identified and then analysed for microscopic study. For making microscopic slides, 1 or 2 leaves were taken in a test tube and dipped in 30% nitric acid and 70% lactic acid for few minutes, and then placed on petri plates for separating the epidermis. Numerous quantitative and qualitative foliar anatomical features of adaxial and abaxial surfaces, including epidermal cell shapes, stomata size, subsidiary cell size, the pattern of the anticlinal wall, the morphology of the stomatal complex and trichome diversity, were examined. A small number of the considered species had anomocytic and anisocytic stomata; a few species had paracytic stomata, for instance, Ricinus communis, Euphorbia royleana, Buxus pilosula and Sorghum halepense; and only Ipomoea carnea had cyclocytic stomata in the studied taxa. The epidermal cells of the analysed species were irregular, while some exhibited polygonal, wavy, tetragonal and elongated cell morphologies. Overall, this study emphasises the significance of foliar micromorphology analysis as a valuable resource for identifying potentially poisonous plants and demonstrates its contribution to maintaining public welfare, thereby benefitting public health and safety.

Keywords

• biodiversity
• foliar epidermis
• microanatomy
• stellate trichomes
• taxonomy