MICROSCOPIC CHARACTERISTICS AND LEAF CONSTANT NUMBERS OF SELECTED DERRIS SPECIES IN THAILAND

Medicinal plant identification is necessary for ensuring their efficacy and safety in the quality control of herbal products. The genus Derris belongs to the Leguminosae family. This study aimed to investigate the microscopic characteristics of selected Derris species in Thailand. Eight Derris species (D. amoena, D. elliptica, D. indica, D. malaccensis, D. recticulata, D. scandens, D. solorioides, and D. trifoliata) existing in Thailand were studied. Anatomical characteristics of the leaves were investigated by the midrib transverse section. The laminae were quantitatively investigated for the stomatal number, stomatal index, epidermal cell area, vein islet number, trichome number, and palisade ratio. Trichomes were found in 4 species (D. elliptica, D. scanden, D. amoena and D. malaccensis) which presented as unicellular non-glandular trichome on the lower epidermis. Stomatal type found in Derris species in this study was paracytic type and presented only on lower epidermis, except D. trifoliata which was found on both lower and upper epidermis. The anatomical characteristics of the midrib of eight studied Derris species were illustrated, showing the distinguish anatomy. Leaf constant numbers were demonstrated D. recticulata showed the highest stomatal index (20.21 ± 1.53) and upper epidermal cell area (1172.99 ± 56.25).