Identification of seven Zingiberaceous species based on comparative anatomy of microscopic characteristics of seeds

BACKGROUND The fruits and seeds of Alpinia galanga (L.) Willd., Alpinia katsumadai Hayata, Alpinia zerumbet (Pers.) Burtt. & Smith, Amomum kravanh Pierre ex Gagnep., Amomum subulatum Roxb., Amomum tsao-ko Crevost et Lemaire, and Elettaria cardamomum (L.) Maton from Alpinia, Amomum, and Elettaria genera in the Zingiberaceae family are difficult to distinguish between each other. This study aims to identify the seeds of these seven species from Zingiberaceae family based on comparative anatomy of microscopic characteristics. METHODS We compared the morphological structures of seed coats by observing the microscopic characteristics of seeds in transverse sections. We described the macroscopic characteristics of seeds in detail. RESULTS The seeds of these three genera could not be identified to the species level based on their macroscopic features. However, based on the anatomical features of the seed coat observed in transverse sections, a dichotomous key for these seven species was feasible. CONCLUSION Seven species in the Zingiberaceae family could be identified based on comparative anatomy of microscopic characteristics of transverse section of seed.