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Friday, July 19, 2024

Science Scene

Virulent wheat fungus spreads into Iran

Puccinia graminis, or Ug99, previously found in East Africa and Yemen, has spread to the bread basket of Iran, putting countries east of Iran at risk.

Approximately 80 percent of the wheat varieties grown in Afghanistan, India, Pakistan, Turkmenistan, Uzbekistan and Kazakhstan are susceptible to the fungus, which is capable of decimating entire fields of wheat.

The spores of the fungus are spread by the wind, which allows it to spread rapidly. It first emerged in Uganda and so was named Ug99. It then spread to Kenya and Ethiopia. In 2007, the United Nation Food and Agricultural Organization reported that it had spread to Yemen and that the strain there was even more virulent. Kenya and Ethiopia experienced severe shortages of wheat in 2007 due to the fungus.

Crop breeding is already underway to develop resistance to the virus. The Borlaug Global Rust Initiative is supporting countries affected by the fungus to develop resistant varieties and to produce seeds free of the fungus. (sciencedaily.com)

Stonehenge being excavated

Two researchers, funded by the British Broadcasting Company (BBC), have begun to excavate Stonehenge, looking for a sample of carbon to date Stonehenge. A film crew from the BBC’s show Timewatch will capture the two-week excavation for a show to be broadcast in the fall.

The last dig within the monument happened in 1964. In the 1990s, researchers tried to date the monument but due to poor record keeping of where samples were taken, the date of 2550 B.C. is only approximate.

Stonehenge was originally made up of a ring of stones called bluestones that were brought from the Preseli Hills in Wales, 155 miles away. These stones, smaller than the iconic sarsen pillars, might have been thought to have magical properties of healing, perhaps making the site a place of pilgrimage. Excavated bodies showing signs of traveling long distances to the site and suffering from skeletal trauma provide some support for this hypothesis.

Though the original bluestones have now been removed and have been replaced by replicas, the researchers hope to find shards of them in a 3.5 by 2.5 meter trench they’ve dug. (news.bbc.co.uk)

New fingerprinting technique for bacteria

As genetically engineered bacteria are in high demand, making useful things such as fuels and pharmaceuticals, the potential for their escape into the larger environment increases. Researchers have now found a way to quickly identify these bacteria using software to search the bacteria’s DNA.

Small rings of DNA, called plasmids, are often used to introduce foreign genes to bacteria. New designs of plasmids can be made, but they are often based on older designs, conserving much of the DNA sequence.

A team of researchers at Lawrence Livermore National Laboratory, in Livermore, Calif., reasoned that the common DNA could help identify artificial bacteria. They entered in the DNA sequences of 3,799 plasmids into an automated search tool and identified hundreds of common DNA sequences. The program then computed the smallest set of common DNA between all the plasmids.

This sequence could distinguish 98 percent of the artificial bacteria from non-altered bacteria with no false positives. The results are published in the March issue of Genome Biology. (sciencenews.org)

Science Scene is compiled by JENNIFER WOLF, who can be reached at science@californiaaggie.com.


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