Macroscopic-microscopic characteristics and AFLP fingerprint for identification of Erythroxylum novogranatense, E. cambodianum and E. cuneatum endemic to Thailand

Abstract

Erythroxylum novogranatense (Morris) Hieron, E. cambodianum Pierre and E. cuneatum (Miq.) Kurz in family Erythroxylaceae was traditionally used as an antipyretic, general stimulant and gastrointestinal diseases. Due to their morphological similarity, the correct identification was necessary for the quality control in herbal medicine. E. novogranatense (Morris) Hieron, E. cambodianum Pierre and E. cuneatum (Miq.) Macroscopic and microscopic characteristics evaluated Kurz endemic to Thailand according to WHO standard guideline and amplified fragment length polymorphism (AFLP) fingerprint. Morphological characters of E. novogranatense, E. cambodianum and E. cuneatum were similar in their flower, fruit and seed but different in stem and leaf. Microscopic characteristics from these three species, including constant leaf numbers, showed individual values. The stomata were classified as paracytic type. The midrib transverse section showed distinct characters of the epidermis, palisade cell, stomata, spongy cell, parenchyma, xylem vessel, phloem tissue and collenchyma. AFLP fingerprint showed highly polymorphisms 97.42% with the number of bands (349 bands) ranging between 50-750 bands. Primer E+ACG/M+CTT had the highest number of AFLP band (91 bands). The dendrogram generated from UPGMA could separate these three species. In summary, the combination of morphological characteristics, microscopic investigation and AFLP fingerprinting can be used to identify plant species and determine the genetic relationship among three Erythroxylum species.