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Read the text and answer the questions that follow.






Nature + Science = New Crops

About 6, 000 years ago, according to archaeological evidence, prehistoric farmers in the Americas cross-bred corn plants to create a crop with desirable traits that originally occurred in only a few plants. Centuries later, a 19th-century Austrian priest, Gregor Johann Mendel, experimented with tens of thousands of pea plants and identified the laws of cross breeding plants. The significance of his work was only properly recognized in the early 20th century when Mendel’s Laws of Inheritance became a touchstone for the new science of genetics.

Today, most of the world’s major food crops are grown from hybrid strains. Genetic science has advanced with the emergence of biotechnology and the creation of genetically modified organisms (GMOs). Though these technologies have been controversial, and adamantly opposed by some, many respected scientists assert that developing plants genetically capable of producing greater yields with less fertilizer and water is necessary to meet the food needs of the future. Regardless of how the controversy over genetic engineering is resolved, there is no question that humans have a long history in the manipulation of plant species, resulting in greater abundance and variety in the modern diet.

Here are some examples of the how science works to give food crops qualities that nature overlooked.

Pearl millet is a staple crop for people in the semi-arid tropics. The plants in this field in southern India have been genetically engineered to resist diseases that can kill an entire crop.

The Galaxy peach, also known as the Bagel peach for its flat shape, is a variety developed over 10 years of testing by the U.S. Agriculture Research Service. The sweet taste of the fruit and abundant yield of the tree have made it popular for backyard gardeners.

Nectarines roll down a packing line in a California plant. The nectarine is a natural mutant of the peach with the difference of only a single gene that results in a smooth skin. The peach is thought to have originated in China, but traders introduced it to the West perhaps as long as 2, 000 years ago.

The pluot is a fruit created through cross-breeding plums and apricots in a three-to-one ratio. The aprium is a genetically engineered fruit, also made through a mix of genetic material from plums and apricots, in a one-to-three ratio, creating a fruit that is subtly different in appearance and taste.

The Bribi Indians of Costa Rica have adopted new agricultural methods and varieties of disease resistant crops developed by researchers at the University of Costa Rica.

Plant physiologist Athanasios Theologis isolated and cloned the tomato’s ripening gene. By manipulating this gene, Theologis and others created the Endless Summer tomato, a variety that can be left on the vine long enough to develop full taste and texture while still remaining ripe when it arrives at the supermarket.

In Guinea researchers created Nerica, “new rice for Africa” by crossbreeding an African rice variety with another variety that resulted in a more productive strain. The plant provides growers with greater yields to sell and thus increases their incomes.

From eJournal USA, 21st Century Agriculture

Questions:

1) How old is cross-breeding?

2) What role did Gregor Johann Mendel play in the history of genetics?

3) How often is cross breeding and genetic engineering used today?

4) What are GMOs? Why are they created?

5) Is genetic engineering accepted by everyone?

6) Give examples of new plant species created with the help of science. What new qualities are introduced in them?

7) Have you ever eaten any of the foods mentioned above?

8) What is your attitude to: cross-breeding, genetic engineering, GMOs? Give reasons.


ADDITIONAL READING – 3


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