XVI International Botanical Congess

By regular long-term investigations and the publication analysis the information about the compound apertures types of pollen of more than 200 dicotyledons families has been generalized. In the compound apertures structure 4 components are accepted: colpus, pore, ore and infracolpus differing from each other in respect of both structure and function. Various combinations of the components cause diverse compound aperture types: colp-porate, colp-orate, colp-pore-orate and colp-infracolp-pore-orate. Such an approach allowed to trace possible evolutionary ways and levels within the compound apertures types. In the presence of 3 levels of the compound apertures evolution 2 main evolutionary trends have been established: long-colpate (with a considerable tendency towards the further complication) and short-colpate leading in the end to the porate aperture type formation.