Camelina, a modern-day Ukrainian oilseed plant, may have been a more important and widespread crop than previously thought. The new findings could help breeders improve this crop for biofuels applications. Camelina, also known as false flax or Gold-of-Pleasure, is an ancient oilseed crop that is finding new uses in the production of low-input, sustainable biofuels.
Washington University in St. Louis’ multidisciplinary research is revealing the origins and uses of camelina and may help guide decisions critical to realizing its potential as a biofuel feedstock for a greener aviation industry in the future.
During his time as a graduate student at Washington University, biologist Jordan Brock went on several field expeditions to collect wild camelina, including one trip to Ukraine as a National Geographic Explorer. “Seeing how rural people in Ukraine were continuing to grow camelina, a crop that had been lost almost throughout Europe, was especially valuable to me,” Brock said.
According to Brock’s new study in the American Journal of Botany, co-authored by Melissa Ritchey, a PhD candidate in anthropology, and Kenneth M. Olsen, professor of biology, both in Arts & Sciences at Washington University, cameelina may have been a more important and widespread crop than previously thought.
“By combining multiple lines of evidence, in this case archaeological and genetic,” Ritchey explained, “we can gain much clearer understandings of the history of crop domestication and trace the declines and increases in their use over time.”
The researchers determined that camelina was likely domesticated around 6,000 to 8,000 years ago in the Caucasus region near what is now known as Armenia. According to the researchers, breeding programs to improve this crop for biofuels applications should take into account the high levels of genetic diversity found in its wild progenitor, Camelina microcarpa, in Western Asia and the Caucasus region.
By combining multiple lines of evidence, in this case archaeological and genetic, we can gain much clearer understandings of the history of crop domestication and trace the declines and increases in their use over time.
Melissa Ritchey
An ancient crop
Camelina has a long history as a European oilseed crop, but it is still poorly understood in many ways. Camellina seeds were stored separately from flax seeds in early Iron Age archaeological sites, indicating that they were cultivated separately. Camelina was grown throughout the Roman empire and into the early twentieth century.
In the 1930s and 1940s, most Western European countries stopped cultivating camelina, but crop scientists and farmers in Russia, Sweden, and Denmark continued to cultivate and conduct field trials with camelina.
The Washington University researchers examined population structure within the crop species and its relationship to populations of its wild progenitor using genotyping-by-sequencing of 185 accessions, or samples taken from a specific location, of Camelina sativa and its wild relatives. In a separate study, they combed the archaeological literature for sites with archaeobotanical camelina remains and assessed the timing and prevalence of usage in Europe and Western Asia.
“The vast majority of data in archaeobotany comes from charred plant remains,” Ritchey explained. “Unfortunately, the high oil content of oilseeds like camelina causes them to be destroyed rather than charred when they come into contact with fire. However, I was still able to find a lot of data, which gave us the information we needed.”
“There were also a number of camelina ‘cakes’ found in Viking and Iron Age sites in northern Europe which are really cool!” she said.
Ritchey also uncovered records of camelina from Gordion in Turkey, a UNESCO World Heritage site, and Kumtepe, a Neolithic settlement that is considered the oldest permanent settlement in the Troas, the region in northwestern Anatolia, where Troy was later built.
Archaeologists have long theorized that camelina was domesticated in the regions around Armenia, while plant geneticists had entertained different, competing hypotheses for the plant’s origins as a crop.
Ritchey said: “Through our analyses, we were able to test these hypotheses and provide a clearer consensus on the earliest domesticated appearances in Armenia.”
New interest for biofuels applications
The renewed interest in camelina has resulted in a significant increase in molecular-based research on camelina and how to improve it. Because of the short growing season and low input requirements, camelina could be a valuable crop in areas where there are few alternatives. Camelina can be grown in marginal soils, which means farmers may be able to cultivate it on neglected or otherwise unarable land.
These characteristics may be improved through breeding or genetic modification. However, the crop’s lack of diversity in modern cultivars makes this prospect more difficult.
Camelina sativa is also known as false flax or Gold-of-Pleasure. Research from Washington University in St. Louis shows that camelina may have been a more important and widespread crop than previously thought. (Image: Shutterstock)
“Unfortunately, the low genetic diversity present in modern cultivars is presenting challenges to breeders who are looking for genetic variation and agricultural traits (increased yield, higher disease resistance, drought tolerance, etc.), which they may use for breeding better camelina cultivars,” Brock said.
“Understanding the domestication history of camelina is an important and timely discovery because this effort has identified where novel wild diversity is present, especially in Georgia and Armenia,” Brock said. “This could prove to be a solution to the challenges of low genetic diversity in the crop.”
The payoff could be large, both for farmers interested in traditional food uses and for those who want to expand the use of camelina as a biofuels feedstock.
“Ultimately, its use as an aviation biofuel would be the biggest game changer, as airline companies can use camelina-derived jet fuel to reduce carbon emissions and make flying more sustainable,” said Brock, who is now a National Science Foundation (NSF) postdoctoral research associate at Michigan State University. “Camelina-derived jet fuel has already been tested by the US Air Force and in commercial aircraft, resulting in significantly lower emissions.”
“Camelina oil blends have demonstrated viability,” he said. “The next challenge is increasing field production and crop yield.”
