Abstract: The floral organogenesis of Triglochin maritimum Linn. was observed under scannning electron microscope (SEM). Floral development of T. maritimum consists of the sequential initiation of alternating, trimerous whorls of floral appendages in centripetal and acropetal succession: two whorls of tepals, two of stamens, and two of carpels in the typical monocotyledonous pattern. Our observation did not find an association of the tepal and stamen primordia (the “CA complex”). The common base of the stamen and its opposing tepal in later stage maybe a result of subsequent intercarary upgrowth, which is secondary result. There are differences in position, timing and rates of development between whorl of tepals and stamens. Differential timing and rates of growth of the inner tepals and outer stamens result in the former appearing to be located internal to the latter in the mature flower. In the late stage of floral development, we observed the decreasing case of the number of carpel. It seems that the present observation of T. maritimum does not support the interpretation of the flower of Triglochin as a reduced lateral branch of the inflorescence, though a more detailed study would be requried to confirm this.

Key words: Triglochin maritimum, floral organogenesis, Juncaginaceae