Dodder on heather and gorse.
|From an article in New Scientist, 25
Aug 2012, p.36.|
The parasitic vine called dodder is the sniffer-dog of the vegetable world. It contains almost no chlorophyll - the pigment that most plants use to make food - so to eat it must suck the sugary sap from other plants. Dodder uses olfaction to hunt down its quarry. It can distinguish potential victims from their smell, homing in on its favourites and also using scents emitted by unhealthy specimens to avoid them (Science, vol 313, p.1964)
Dodder is exceptionally sensitive to odours, but all plants have a sense of smell. In animals, sensors in the nose recognise and bind with molecules in the air. Plants also have receptors that respond to volatile chemicals.