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[Gene GeRue <genegerue AT ruralize.com>]

Thank goodness for scientists. I was freaking out thinking about all  
the pain I was bringing into the world each time I clipped some basil.  
Can we now put to rest that business about plants suffering agonies  
when we eat them?

On the other hand, I am becoming nervous thinking that maybe veggies  
are conspiring to do me in. Just when you think you have some part of  
life in hand you get these sassy scientists creating doubt and  
confusion. Plants taking over the Universe? Don't be too quickly  
dismissive.

Plants used to seem benign. Now they are becoming scary. Better not  
whiz them off. Seems to me the safe thing is to just eat pretzels and  
drink beer.

Plants make their own painkillers
Aspirinlike substance may soothe stress and signal alarm to other plants
By Andrea Thompson
Senior writer

When you have a headache, you take a couple of aspirin, but when  
plants get stressed out, they just make their own.

Scientists had known that plants in laboratories produce a chemical  
called methyl salicylate — a form of the painkiller aspirin — when  
stressed out, but they had never detected it in plants out in nature.

A team of scientists from the National Center for Atmospheric Research  
in Boulder, Colo., discovered by accident plants in the wild emitting  
methyl salicylate. They set up instruments last year in a walnut grove  
near Davis, Calif., to monitor plant emissions of certain volatile  
organic compounds, or VOCs. Such compounds emitted by plants can  
actually combine with industrial emissions and contribute to smog.

To their surprise, the NCAR scientists found that the emissions of  
VOCs their instruments recorded in the atmosphere included methyl  
salicylate.

They noticed that the methyl salicylate emissions increased  
dramatically when the plants, already stressed by a local drought,  
experienced unseasonably cool nighttime temperatures followed by large  
temperature increases during the day.

Scientists think that the methyl salicylate has two functions:  
stimulating a process similar to the immune response in animals that  
helps plants resist and recover from disease, and acting as a form of  
chemical communication to warn neighbors of threats.

"These findings show tangible proof that plant-to-plant communication  
occurs on the ecosystem level," said study team member Alex Guenther.  
"It appears that plants have the ability to communicate through the  
atmosphere."

The research, funded by the National Science Foundation and detailed  
in the Sept. 8 issue of the journal Biogeosciences, could give farmers  
and forest managers an early warning signal that all is not right with  
their plants, either because of disease, insect infestation, or other  
types of stress.

"The earlier you can detect that something's going on, the more you  
can benefit in terms of using fewer pesticides and managing crops  
better," said study leader Thomas Karl.

Methyl salicylate and other plant hormones emitted into the atmosphere  
could also account for some of the fraction of VOCs scientists had  
suspected were in the atmosphere but had escaped detection until now.