歌词
From VOA Learning English,
this is the Agriculture Report.
The World Food Prize has been awarded to three developers
of genetically modified crops,or GMOs.
Mary-Dell Chilton, Marc van Montagu and Rob Fraley
received the award on October 17th.
The award praises the technology they created
for being able to increase the quantity
and availability of food,
it also says GMOs help deal with a growing world population
and changes in weather patterns.
But the selection of the three scientists
has been criticized by people
who question the safety and value of GMOs.
In the 1970s, Marc van Montagu,
a Belgian scientist discovered bacteria in soil
performing a kind of natural genetic engineering.
He found that the bacteria placed a piece of
their genetic material, or DNA inside the plant cells,
the cells then produce chemicals
that work good for the bacteria.
"Once we [saw] bacteria can insert DNA
to give a new property to a plant,
we were able to replace that part of the DNA [with] DNA
that we want that gives new,
useful properties to the plant," van Montagu said.
His work was the beginning of plant biotechnology.
Mary-Dell Chilton and Rob Fraley both Americans,
produced the first genetically modified plants using that technology.
Ms Chilton was studying a common plant infection called crown gall
when she witnessed the same thing as Mr van Montagu.
She discovered that it forms when a germ called Agrobacterium
puts a piece of its own DNA into the plant cell's genes,
the plant then makes food for the bacteria.
Ms Chilton, Mr van Montagu and Mr Fraley
along with the Monsanto company created the technology
to reproduce plants while changing their DNA.
Genetic engineering can add information to plants
to produce different kinds of things,
such as a protein that kills insects.
Farmers quickly accepted and supported the new technology
first used in 1996.
Nearly all the corn and cotton
grown in the United States is made with GMOs.
The World Food Prize organization in the American state of IOWA says
17 million farmers worldwide grew GMO crops in 2012.
It says the technology increased production
and reduced the usage of harmful chemical on crops.
Doug Gurian-Sherman is a scientist with the Union of Concerned Scientists.
He says the technology could be useful,
but as there is no proof it is necessary to feed the world.
"My understanding of the prize is you should be giving it to people
that have shown major positive,
unequivocally positive accomplishments in world agriculture.
And I don't see, so far,
this technology being anywhere near that yet," Gurian-Sherman said.
Opposition to GMOs is also spreading.
In the Philippines, protesters destroyed test fields of rice
that had been genetically engineered to produce vitamin A.
And that's the Agriculture Report from VOA Learning English.
I'm Christopher Cruise.
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