问题详情

Even plants can run a fever, especially when they are under attack by insects or disease.But【21】______ humans, plants can have their temperature 【22】______ from 3,000 feet away— straight up. A decade ago, 【23】______ the infrared(红外线的)scanning technology developed for military purpose and other satellites, physicist Stephen Paley 【24】______ a quick way to take the temperature of crops to determine 【25】______ ones are under stress. The goal was to let farmer 【26】______ target pesticide spraying 【27】______ rain poison on a whole field, which 【28】______ include plants that don"t have the pest problem.
Even better, Paley"s Remote Scanning Services Company could detect crop problem before they became 【29】______ to the eye. Mounted on a plane flown at 3,000 feet 【30】______ , an infrared scanner measured the heat emitted by crops. The data were 【31】______ into a color-coded map showing 【32】______ plants were running "fevers". Farmers could then spot spray, using 50 to 70 percent less pesticide than they 【33】______ would.
The bad news is that Paley"s company closed down in 1984, after only three years. Farmers 【34】______ the new technology and long-term backers were hard 【35】______ . But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to 【36】______ into operation. Agriculture experts have no doubt the technology works. "This technique can be used 【37】______ 75 percent of agricultural land in the United States," says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Depart ment of Agriculture, thinks 【38】______ infrared crop scanning could be adopted by the end of the decade. But 【39】______ Paley finds the financial backing 【40】______ he failed to obtain 10 years ago.
【21】
A．as
B．with
C．like
D．unlike