For allergy sufferers, the pollination period is a tough time, whereas for plants it is the opportunity to reproduce: in addition to the wind, insects, in particular, carry the pollen from one flower to another to pollinate them.
For allergy sufferers, the pollination period is a tough time, whereas for plants it is the opportunity to reproduce: in addition to the wind, insects, in particular, carry the pollen from one flower to another to pollinate them. During this transport, the pollen must repeatedly attach to and detach from different surfaces. To date, the underlying adhesive mechanisms have hardly been studied so far. Now, scientists from the Zoological Instituteat Kiel University (CAU) have discovered that the mechanisms are far more complex than previously assumed. They differ depending on the duration of the contact and the microstructure of the surfaces. In their study presented in the current issue of the Journal of the Royal Society Interface, they found a unique pollen gripping mechanism on the receptive female part of plants for the first time. The results could provide important knowledge for the transport of medicinal substances, and also - in light of the alarming decline in insect populations - for the development of alternative strategies in agriculture and food production.
Pollen: an all-round adhesive talent
Itchy nose, red eyes, constant sneezing - materials scientist Shuto Ito suffered from a severe pollen allergy. To learn more about the process of pollen dispersal he left his hometown in Japan to study the adhesive properties of pollen under Professor Stanislav Gorb at Kiel University. Bionics researcher Gorb and his working group "Functional Morphology and Biomechanics" investigate the special abilities of plants and animals, and how these can be imitated artificially.
"If pollen is transported by insects from flower to flower, it encounters three different types of surfaces to which it must attach itself and then detach again. We want to find out which adhesive mechanisms enable this," explained Gorb. Doctoral researcher Ito investigates these mechanisms using as a model species Hypochaeris radicata, also known as common cat’s-ear (or false dandelion). This species within the family of the composite plants blooms from spring to late autumn in the entire northern hemisphere. As with many other plants, the pollen on their yellow flowers is covered with an oily substance known as pollenkitt. "Until now, scientists believed that pollenkitt has a central adhesive function. But we have found out that under certain conditions it behaves in exactly the opposite way. We must consider the adhesive mechanisms in a much more differentiated manner," Ito summarised the findings thus far. Accordingly, pollen adhesion is influenced by a complex interplay of the age of the pollen, the humidity and the respective surfaces for adhesion.
Read more at: Kiel University
Colored cryo-SEM image of stigma of Hypochaeris radicata (Photo Credit: © Shuto Ito)
