Aerobiology of pteridophyta spores: Preliminary results and applications

Abstract

Pteridophyte airborne spores are scarcely represented worldwide compared to fungal spores or even to pollen grains. However, the levels of fern spores in the atmosphere are connected to the distribution and abundance of different Pteridophyta species, being tropical and subtropical zones of Asia, America and Africa, the areas where fern spores are most abundant. Their seasonal distribution includes all the months in tropical zones, according to the continuous sporing process that usually occurs because of the sequential development of sporangia in the different fern species. In temperate areas, the presence of airborne spores is located in late Summer and early Autumn. In addition, there are few studies reporting information about hourly distribution of fern spores in the atmosphere, in which bracken spores were mainly observed at midday when spore traps are located near to fern formations. Airborne spore concentrations are also higher in near zones of fern populations and lower when spore traps move away of these zones, being registered processes of transport.