MORPHOLOGICAL STRUCTURE OF THE INFLORESCENCE IN GLADIOLUS IMBRICATUS L. AND IRIS SIBIRICA L. (IRIDACEAE)

Abstract

In the bracteose inflorescence of Gladiolus imbricatus and Iris sibirica, the distichous phyllotaxis and different level of morphological polyvariance were revealed. The spike-like inflorescence of Gladiolus imbricatus is composed of 8–14 flowers, all of them are turned to the same side during flowering. The inflorescence of Gladiolus imbricatus reveals morphological invariance and represents a simple spike-like raceme with flo­wers placed on very short pedicels. The bracts and prophylls in the inflorescence of Gladiolus imbricatus retain throughout the genesis. The inflorescence of Iris sibirica is composed of 1–3 rhipidia and reveals a high level of morphological polyvariance after the number of flowers, their location and flowering order. The most common is five-flowered inflorescence in two rhipidia. The spathae of rhipidia fall down at the beginning of flowering while bracts retain till the middle-time of fruit ripening. All leaves in the inflorescence of Iris sibirica except bracts of the lowest flowers of rhipidia, have prophyll structure. In the inflorescence of both species, the rudimental flowers were found, that are evidence of the potential larger size of the ancestral inflorescence.