Washington, September 5 : Using a scanning electron microscope to peer at the structures of rose petals, chemists at Tsinghua University in Beijing have found that a carpet of minuscule bumps covered with even tinier ridges makes the dewdrops stick to the flower. Study leader Lin Feng says that this finding is at variance with the proposition that the chemical makeup of the petals grips the water droplets.
During the study, Feng's team made a plastic cast of the petal surface. As with the original petal, water droplets stuck to the cast, even when it was turned upside down.
The researcher says that it is the texture that does the trick, reports Live Science.
Feng adds that texture is also important in the so-called "lotus effect" that causes water to bead up and roll off many plants' leaves and petals, clearing away dust and debris.
The team say that on drop-shedding surfaces, the tiny bumps have wax-coated tips and are separated by narrower troughs, which is why they make less contact with water.
According to Feng, the rose's waxless "petal effect" may enable the flower to attract pollinators by holding glistening dewdrops.
The study has been published in the journal Langmuir.