Zombies in the garden are slowly killing plants
Scientists say they have identified a protein that causes zombielike behavior in plants. Certain crops are vulnerable to parasites that take control of their hosts’ behavior, forcing them to act in the intruders’ interest.
The phenomenon occurs in flowering plants that have been infected by a pathogen transmitted by the tiny insects called leafhoppers. Rather than grow petals or stamens, infected plants will produce green, leaflike structures. This benefits the leafhoppers, which can eat the leaflike growths, but it prevents the plants from reproducing.
“It is like a living death for the plant,” said Saskia A. Hogenhout, a biologist at the John Innes Center in England and an author of the study, which appears in the journal PLOS Biology. Affected crops can include grapes, coconuts and rapeseed.
By sequencing the genome of the pathogen, researchers identified a protein, SAP54, that causes the plants to produce the leaf tissue rather than their intended flowers. To become active, SAP54 interacts with a family of plant proteins known as RAD23.
Fruit flies maneuver like tiny helicopters
Apparently it is not just speed that makes a fly so hard to swat. In the face of danger, fruit flies execute surprisingly nimble maneuvers to pitch and roll out of harm’s way.
Using high-speed cameras and a large robotic fly, scientists analyzed the movements of nearly 100 fruit flies that encountered threats midflight. They found that instead of turning by simply rotating on their vertical axis like a plane – the way fruit flies had been thought to do during normal flight – the flies execute a series of rapid banked turns that allow them to quickly change direction and escape the danger.
“They’re like little tiny helicopters,” said Michael Dickinson, a biologist at University of Washington and an author of the study. “They roll over or pitch backward very quickly so they’re facing a different direction, then zip off in that direction.”
The maneuvers require only tiny changes in wing motion, he added, but remarkably fast processing.
“What was really surprising was how fast the flies take the information from their visual system and give the right commands to the motor system,” he said.
The study, which was published in the journal Science, is the latest to use high-speed imagery and robot simulations to reveal the intricate flying abilities of winged insects.
– New York Times