Even plants can run a fever, especially when they"re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away-straight up.
A decade ago, adapting the infrared (红外线) scanning technology developed for military
purposes and other satellites, physicist Stephen Paley came up with a quick way to take the
temperature of crops to determine which ones are under stress. The goal was to let farmers
precisely target pesticide (杀虫剂) s
praying rather than rain poison on a whole field, which
invariably includes plants that don"t have pest problems.
Even better, Paley"s Remote Scanning Services Company could detect crop problems
before they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an
infrared scanner measured the heat emitted by crops. The data were transformed into a
color-coded map showing where plants were running "fevers". Farmers could then spot-spray,
using 50 to 70 percent less pesticide than they otherwise would.
The bad news is that Paley"s company closed down in l984, after only three years. Farmers
resisted the new technology and long-term backers were hard to find. But with the renewed
concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get
back into operation. Agriculture experts have no doubt the technology works. "This technique
can be used on 75 percent of agricultural land in the United States", says George Oerther of
Texas A & M. Ray Jackson, who recently retired from the Department of Agriculture, thinks
remote infrared crop scanning could be adopted by the end of the decade. But only if Paley
finds the financial backing which he failed to obtain 10 years ago.