Navigation Links
Using DNA, scientists hunt for the roots of the modern potato

MADISON -More than 99 percent of all modern potato varieties planted today are the direct descendents of varieties that once grew in the lowlands of south-central Chile. How Chilean germplasm came to dominate the modern potato-which spread worldwide from Europe-has been the subject of a long, contentious debate among scientists.

While some plant scientists have maintained that Chilean potatoes were the first to be planted in Europe, a more widely accepted story holds that European potatoes were originally descended from plants grown high in the Andes mountains between eastern Venezuela and northern Argentina. According to this theory, Andean potatoes were wiped out during the Great Irish Potato Famine, the 19th-century late-blight epidemic that devastated potato fields across Europe, initiating the import of Chilean varieties to re-establish the crop.

In a report published today in the American Journal of Botany, University of Wisconsin-Madison researchers Mercedes Ames and David Spooner say both theories are wrong. By analyzing the DNA of historical potato specimens, the researchers found that both Chilean and Andean potatoes were grown in Europe decades before and decades after the famine, the first direct evidence that the potatoes were grown simultaneously in Europe.

"Basically, we found that the Andean potatoes got to Europe first, around 1700. However, Chilean potatoes were starting to get popular there 34 years before the late blight epidemic," says Ames, a graduate student in UW-Madison's plant breeding and plant genetics program. The results also show that Andean potatoes grew as late as 1892 in Europe, proving they weren't polished off by the late blight epidemic-and that they grew side by side with Chilean potatoes for many decades before the Chilean types became dominant.

To start the project, which was funded by the National Science Foundation, Ames visited herbaria throughout Europe in search of early potato specimens. She requested hole-punch sized samples of dried leaf tissue from appropriate specimens be sent to Madison for study, eventually ending up with material from 64 potato plants grown between 1700 and 1910.

"Some of these samples were over 300 years old and not ideally preserved," says Spooner, a professor of horticulture and USDA researcher who is the paper's corresponding author. "It took considerable innovation for Mercedes to work out the correct technique to get DNA from them."

After successfully extracting DNA from 49 samples, Ames analyzed each using a DNA marker that distinguishes between upland Andean and lowland Chilean potato types. The result is a biochemical record of ancestry, which Spooner says adds hard evidence to a debate often premised on guesswork.

"The problem with these two theories is that they rely on inferences based on the morphology of old plant samples, as well as inferences based on historical records about day-length adaptation, shipping routes, and the role of the late blight epidemic," he says. "Our work is the first direct evidence-as opposed to the inferential evidence used in prior studies-on the origin of the European potato because the herbarium specimens we used are like fossils."

Spooner notes that this type of analysis could help set the record straight for many other crop species. "Potato is one of the prominent stories in crop evolution books," says Spooner. "Because of Mercedes's work, they're going to have to rewrite the textbooks."


Contact: David Spooner
University of Wisconsin-Madison

Related biology news :

1. U of M begins nations first clinical trial using T-reg cells from cord blood in leukemia treatment
2. Fever causing headaches for Aussie parents
3. Using evolution, UW team creates a template for many new therapeutic agents
4. Using green chemistry to deliver cutting-edge drugs
5. IGERT fellows to design biodevices using flexible electronics
6. Prediction of RNA pseudoknots using heuristic modeling with mapping and sequential folding
7. Computer program traces ancestry using anonymous DNA samples
8. Using nanotubes to detect and repair cracks in aircraft wings, other structures
9. Book on weeds and invasive plants discusses how to manage them using ecological approaches
10. Study shows housing development on the rise near national forests
11. Rare cancer-causing syndrome found, for the first time, in Singapore
Post Your Comments:
(Date:6/22/2016)... 22, 2016  The American College of Medical Genetics and ... Magazine as one of the fastest-growing trade shows during ... the Bellagio in Las Vegas . ... of growth in each of the following categories: net square ... number of attendees. The 2015 ACMG Annual Meeting was ranked ...
(Date:6/21/2016)... , June 21, 2016 NuData ... the new role of principal product architect and ... the director of customer development. Both will report ... technical officer. The moves reflect NuData,s strategic growth ... response to high customer demand and customer focus ...
(Date:6/15/2016)... York , June 15, 2016 ... new market report titled "Gesture Recognition Market by Application ... Forecast, 2016 - 2024". According to the report, the  ... 11.60 billion in 2015 and is estimated to ... USD 48.56 billion by 2024.  Increasing ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... Mass. , June 23, 2016   ... development of novel compounds designed to target cancer ... napabucasin, has been granted Orphan Drug Designation from ... the treatment of gastric cancer, including gastroesophageal junction ... stemness inhibitor designed to inhibit cancer stemness pathways ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... Plate® YM (Yeast and Mold) microbial test has received AOAC Research Institute approval ... of microbial tests introduced last year,” stated Bob Salter, Vice President of Regulatory ...
(Date:6/23/2016)... ... June 23, 2016 , ... Supplyframe, the Industry Network ... Supplyframe Design Lab . Located in Pasadena, Calif., the Design Lab’s mission is ... projects are designed, built and brought to market. , The Design Lab is ...
(Date:6/23/2016)... June 23, 2016  Blueprint Bio, a company dedicated ... the medical community, has closed its Series A funding ... . "We have received a commitment from ... we need to meet our current goals," stated ... the runway to complete validation on the current projects ...
Breaking Biology Technology: