Hermodactylus tuberosus L. (Iridaceae) pollen organisation before and after anther dehiscence

The morphology, cytology and viability of Hermodactylus tuberosus L. (Irida cene) pollen were examined from the first mitosis until maturation and afte r anther opening. During maturation, the pollen coat becomes modified, and the vegetative cell cytoplasm accumulates several types of reserve substanc es. In the vegetative cell cytoplasm, starch is quickly utilised whereas li pid inclusions of different dimensions, shape and composition occur during pollen maturation. Pollen from opened anthers have a thin pollen coat; the cytoplasm has mostly lipid reserves, and many small vesicles and vacuoles. It is similar in size or larger than pollen located inside the anther, and its viability does not decrease until one;lay after anther dehiscence. Larg e osmiophilic bodies, different from those of the vegetative cell cytoplasm , are present in the generative cell cytoplasm starting from the first stag e of pollen development. The poorly developed pollen coat in pollen from op ened anthers suggests that it plays a minor role in attracting insects for pollination. The size and structural and ultrastructural features of mature pollen indicate that it does not undergo dehydration and possesses suffici ent vigour for immediate germination.