Abstract

To fulfil scarce and incomplete information on floral micromorphology of ensets (Ensete Bruce ex Horan.) in the banana family (Musaceae), a comparative anatomical study of two species: E. glaucum (Roxb.) Cheesman and E. superbum (Roxb.) Cheesman, native to Thailand was conducted. It was found that, apart from five fertile stamens presented in other members of the Musaceae family, both ensets possess a short staminode. It is suggested from this investigation that six is the basic number of Ensete androecial whorl and the taxa could secure the most primitive status within the family and the Zingiberales order, of which stamen numbers are reduced. The results also indicated that the vascular bundle position in compound tepal, the vascular patterns in vascular zone of ovary and cell shapes of stigma epidermis and the ovary cortex are of systematic significance in conjunction with pollen size and exine ornamentation. These useful micromorphological characters can be further applied for identification of other Ensete species distribute elsewhere in the world.

Keyword: Amphicribal vascular bundle, Anatomical characters, Carpellary dorsal bundle, Floral anatomy, Free tepal, Ginger order, Monocotyledons, Staminal strands, Sterile stamen.