Aperture (botany)

Epilobium pollen has three apertures that are pores

The aperture of Lilium pollen is a single sulcus

Apertures are areas on the walls of a pollen grain, where the wall is thinner and/or softer. For germination it is necessary that the pollen tube can reach out from the inside of the pollen grain and transport the sperm to the egg deep down in the pistil. The apertures are the places where the pollen tube is able to break through the (elsewhere very tough) pollen wall.

The number and configuration of apertures are often very exactly characteristic of different groups of plants. The biggest class of plant species, the Eudicots, usually have three apertures in each pollen grain.

Footnotes

• Ressayre, A; Godelle, B; Mignot, A; Gouyon, Ph (Jul 1998), "A Morphogenetic Model Accounting for Pollen Aperture Pattern in Flowering Plants", Journal of Theoretical Biology 193 (2): 321–334, doi:10.1006/jtbi.1998.0704, PMID 9735262 

Further reading

• Punt, W; Hoen, P; Blackmore, S; Nilsson, S; Lethomas, A (2007), "Glossary of pollen and spore terminology", Review of Palaeobotany and Palynology 143 (1-2): 1, doi:10.1016/j.revpalbo.2006.06.008