Ieltsfever com Academic Reading Practice Test 37


READING PASSAGE 1 Questions 1 - 13



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READING PASSAGE 1 Questions 1 - 13
You should spend about 20 minutes on
Questions 1 – 13
which are based on
Reading Passage 1 below.
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The banana is an excellent case in point. Until the 1950s, one variety, the Gros Michel, 
dominated the world’s commercial business. Found by French botanists in Asia in the 
1820s, the Gros Michel was by all accounts a fine banana, richer and sweeter than 
today’s standard banana, and without the latter’s bitter aftertaste when green. But it 
was vulnerable to a soil fungus that produced a wilt known as Panama disease. “Once 
the fungus gets into the soil, it remains there for many years. There is nothing farmers 
can do. Even chemical spraying wont get rid of it,” says Rodomiro Ortiz, director of the 
international Institute for Tropical Agriculture in Ibadan, Nigeria. So plantation owners 
played a running game, abandoning infested fields and moving to “clean” land – until 
they ran out of clean land in the 1950s and had to abandon the Gros Michel. Its 
successor, and still the reigning commercial king, is the Cavendish banana, a 19
th
century 
British discovery from southern China. The Cavendish is resistance to Panama disease 
and, as a result, it literally saved the international banana industry. During the 1960s, it 
replaced the Gros Michel on supermarket shelves. If you buy a banana today, it is almost 
certainly a Cavendish. But even so, it is a minority in the world’s banana crop. 
Half a billion people in Asia and Africa depend on bananas. Bananas provide the largest 
source of calories and are eaten daily. Its name is synonymous with food. But the day of 
reckoning maybe coming for the Cavendish and its indigenous kin. Another fungal 
disease, Black Sigatoka – which causes brown wounds on leaves and premature fruit 
ripening – cuts fruit yields by 50 to 70% and reduces the productive life of banana plants 
from 30 years to as little as two or three. Commercial growers keep Sigatoka at bay by a 
massive chemical assault. 40 sprayings of fungicide a year is typical. But even so, 
diseases such as Black Sigatoka are getting more and more difficult to control. “As soon 
as you bring in a new fungicide, they develop resistance,” says Frison. “One thing we can 
be sure of is that the Sigatoka won’t lose in the battle.” Pool farmers, who cannot afford 
chemicals, have it even worse. They can do little more than watch their plants die. 
“Most of the banana trees in Amazonia have already been destroyed by the disease” 
says Luadir Gesparotto, Brazil’s leading banana pathologist with the government 
research agency EMBRAPA. Production is likely to fall by 70% as the disease spreads, he 
predicts. The only option would be to find a new variety. 
But how? Almost all edible varieties are susceptible to the diseases, so growers cannot 
simply change to a different banana. With most crops, such a threat would unleash an 
army of breeders, scouring the world for resistant relatives whose traits they can breed 
into commercial varieties. Not so with the banana. Because all edible varieties are 
sterile, bringing in new genetic traits to help cope with pests and dis-eases is nearly 
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impossible. Nearly, but not totally. Very rarely, a sterile banana will experience a genetic
accident that allows an almost normal seed to develop, giving breeders a tiny window
for improvement. Breeders at the Honduran Foundation of Agricultural Research have
tried to exploit this to create disease-resistant varieties. Further backcrossing with wild
bananas yielded a new seedless banana resistant to both black Sigatoka and Panama
disease.
Neither Western supermarket consumers nor peasant growers like the new hybrid. 
Some accuse it of tasting more like an apple than a banana. Not surprisingly, the 
majority of plant breeders have until now turned their backs on the banana and got to 
work on easier plants. And commercial banana companies are now washing their hands 
of the whole breeding effort, preferring to fund a search for new fungicides instead. 
"We supported a breeding programme for 40 years, but it wasn't able to develop an 
alternative to Cavendish. It was very expensive and we got nothing back," says Ronald 
Romero, head of research at Chiquita, one of the Big Three companies that dominate 
the international banana trade. 
Last year, a global consortium of scientists led by Frison announced plans to sequence 
the banana genome within five years. It would be the first edible fruit to be sequenced. 
Well, almost edible. The group will actually be sequencing inedible wild bananas from 
East Asia because many of these are resistant to black Sigatoka. If they can pinpoint the 
genes that help these wild varieties to resist black Sigatoka, the protective genes could 
be introduced into laboratory tissue cultures of cell from edible varieties. These could 
then be propagated into new, resistant plants and passed on to farmers. 
It sounds promising, but the big banana companies have, until now, refused to get 
involved in GM research for fear of alienating their customers. "Biotechnology is 
extremely expensive and there are serious questions about consumer acceptance,” says 
David McLaughlin, Chiquita's senior director for environmental affairs. With scant 
funding from the companies, the banana genome researchers are focusing on the other 
end of the spectrum. Even if they can identify the crucial genes, they will be a long way 
from developing new varieties that smallholders will find suitable and affordable. But 
whatever biotechnology's academic interest, it is the only hope for the banana. Without 
it, banana production worldwide will head into a tailspin We may even see the 
extinction of the banana as both a lifesaver for hungry and impoverished Africans and as 
the most popular product on the world's supermarket shelves. 

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