Active Vocabulary 3
calcium deficiency [ˈkalsɪəm dɪˈfɪʃ(ə)nsi] – недостаток кальция
tuber [ˈtjuːbə] – клубень (картофеля)
low calcium defects [dɪˈfekts] – недостатки (изъяны), связанные с низким содержанием кальция
cosmetic issue |kɒzˈmɛtɪk ˈɪʃuː] – эстетическая сторона вопроса
potato cultivar [ˈkʌltɪvɑː] – сорт картофеля
wild potato [waɪld] – дикий картофель
genes [dʒiːnz] - гены
invaluable resource [ɪnˈvaljʊ(ə)b(ə)l rɪˈsɔːs] – бесценный ресурс
evolve [ɪˈvɒlv] - эволюционировать
breed [briːd] –размножаться, создавать; выводить новые сорта
interbreed [ɪntəˈbriːd] – скрещивать
molecular [məˈlɛkjʊlə] – молекулярный
seedlings [ˈsiːdlɪŋz] – всходы
DNA (deoxyribonucleic acid,) [diˈɑːksiˌraɪboʊnuˈkliːjɪk]- - дезоксирибонуклеиновая кислота (ДНК)
1. Translate the following word combinations into Russian:
Is genetically linked, laborious process, time-consuming, a tremendous amount of time and labor, the resulting generations, wild potato relatives, breeding programs, tuber calcium levels, plant’s calcium trait, a typical breeding program, to make faster progress.
2. Read the following text and say:
a) what the term “high tuber calcium content” means;
b) what subjects are touched upon in the text.
Text 3. Potatoes wild with calcium
Have you ever cut into a potato to find a dark spot or hollow part? Early research shows that these defects are likely the result of calcium deficiencies in the potato and that tuber calcium is genetically linked to tuber quality.
Using this wild variety of potato, Solanum microdontum, researchers found the genetic marker for higher calcium levels
Neither consumers at grocery stores nor the companies that make potato chips and fries want these low calcium defects. In addition to the cosmetic issues, these potatoes are more likely to rot.
Most farmed varieties of potatoes have naturally low levels of calcium. So researchers at the USDA-ARS and University of Wisconsin-Madison looked to wild potatoes. Their purpose: to breed new potato cultivars with high calcium levels.
Many wild potato relatives are still present in South America. Their presence means growers’ potato plants in that region often exchange genes with wild species. That's a way they continue to evolve as the climate changes or as disease and pest patterns change. But (in the United States) potatoes have been removed from that environment. We have to breed new genes in from these wild relatives when we want to improve our cultivars.
These wild relatives are an invaluable resource for scientists across the country. If you go down there and drive along the roadside you can see these weedy, wild plants growing along the roads and fields. The team found a wild potato with almost seven times as much calcium as a usual variety.
The next job was to isolate the calcium trait. Sientists interbred the high- and low-calcium potatoes. The resulting generations showed a ‘molecular marker’—a pattern in the plant’s natural DNA. This pattern led researchers to the plant’s calcium trait.
Finding this marker will allow breeding programs to make faster progress in breeding potato plants with high tuber calcium content. This has been difficult and time-consuming in the past. You have to grow all the populations, harvest tubers, and then analyze the tubers for the trait you are looking at -- in this case tuber calcium levels. And that’s a long, laborious process.
A typical breeding program grows and assesses up to 100,000 seedlings every year. It takes between 10-15 years to release a particular variety of crop plant. However, the process simplifies with known molecular markers. You can collect DNA from seedlings and check for these molecular markers. If you have the marker present, then you select those seedlings and save a tremendous amount of time and labor.
3. Using the text above, finish the following sentences:
1) Early research shows…
2) Neither consumers at grocery stores nor the companies want…
3) Their purpose: to breed…
4) Their presence means…
5) The team found a wild potato with…
6) Finding this marker will allow breeding programs…
7) A typical breeding program grows and assesses up to…
8) The process simplifies with…
4. Answer the following questions:
1) What are the reasons of dark spots and hollow parts inside a potato?
2) Which sorts of potatoes have usually low levels of calcium?
3) What’s the aim of the researches at the University of Wisconsin-Madison?
4) Where are wild potato relatives still present?
5) What will finding the “molecular marker” allow breeding programs to make?
5. Write the summary of the text above.
6. Retell the text “Potatoes wild with calcium”
7. Translate from Russian into English:
1) Исследователи скрестили картофель с высоким и низким содержанием кальция в клубнях.
2) Выращивание картофеля с высоким содержанием кальция было трудным процессом и требовало много времени и усилий.
3) Типичная программа по выведению новых сортов позволила увеличить всхожесть картофеля до 100.000 саженцев в год.
4) ДНК можно получить из всходов, а затем проверить их на наличие так называемых «молекулярных маркеров».
5) Необходимо вывести новые гены из диких сортов картофеля для улучшения сорта.