Identification of selected Jasminum species in Thailand based on microscopic characteristics and RAPD fingerprinting

จาก ChulaPedia

Jasminum, one of the largest genus in family Oleaceae, comprised of more than 200 species. Several species of Jasminum have a long history of usage in traditional medicine, perfumery and flavoring tea. They play an important role in antidepressant, analgesic, anti-inflammatory, antiseptic, and diuretics. Many Jasminum species possess the similar morphology and vernacular name resulting in unintentional substitution. Plant identification plays an important role for herbal usage. Thirty Jasminum accessions in Thailand were investigated for their leaf microscopic characteristics and leaf constants numbers (epidermal cell number, epidermal cell area, stomatal number, stomatal index, palisade ratio, trichome number, vein islet number, and vein termination numbers) as well as RAPD fingerprinting. The microscopic results show anisocytic type of stomata. Two Jasminum accessions (J. funale Decne. subsp. sootepense (Craib) P.S. Green and J. fluminense Vahl subsp. gratissimum) had stomata on both adaxial and abaxial surface of the leaves which can be used for identification of these two accessions whereas the 28 remaining accessions had stomata on abaxial surface. Moreover, J. funale Decne subsp. sootepense, J. humile and J. cordatum had the irregular shape of epidermal cell whereas the lease 27 Jasminum accessions were found in square shape. The present or absent of trichome among 30 Jasminum accessions could be divide into three clusters; cluster 1 had no trichome (4 accessions), cluster 2 had trichome on both adaxial and abaxial surface (5 accessions), and cluster 3 had trichome on abaxial side of the leaf (21 accessions). Combination of several microscopic characteristics and morphology are able to identify Jasminum accessions. Random amplified polymorphic DNA (RAPD) marker was used to generate the phylogenetic relationships among 30 Jasminum accessions. The similarity index ranged from 0.022-0.477. The results from cluster analysis could be divided into 3 groups. In conclusion, leaf microscopic characteristics and leaf constants numbers as well as RAPD fingerprinting can be used to identify 30 Jasminum accessions. Moreover, the data obtained from this study are providing additional information of medicinal plant species.