U professor researches to protect global food supply

David Garvin works with smaller scale versions of wheat, barely and other cash crops.

by Brent Renneke

A new threat to our global food supply is spreading out of Africa, and a professor at the University of Minnesota is working to halt the menace by working with a weed no larger than what you may find in your own front yard. David Garvin, Ph.D., adjunct assistant professor in agronomy and plant genetics , is working with Brachypodium , a grass species native to Europe and Africa, to research methods of disease resistance in crops like barley, oats and wheat. Garvin said Brachypodium serves as a model organism for other, more agriculturally significant grasses. The plantâÄôs 272 million base pairs that make up its DNA were sequenced, which allows scientists to identify the genes of the Brachypodium and the overall processes of the plant, according to Garvin. Garvin said Brachypodium as a model organism allows both him and other scientists to identify the role of the different genes and translate that knowledge to important grain crops. âÄúBy doing that, we are really able to accelerate improvements of next generation crops,âÄù Garvin said. Next generation crops, or future crops, are the major concern for Garvin, who said they may be at risk for diseases like a new variant of the fungus-caused disease called stem rust affecting much of the wheat crops in Eastern Africa and now the Middle East. Garvin said traditional breeding has been successful in the past in building resistance towards stem rust, which can kill up to 80 percent of crops; however, the variation spreading towards Asia is not adhering to that resistance. Garvin said he is now working with Brachypodium to identify genes that are specialized in disease resistance and translating that to wheat, which has an extremely similar genome. âÄúWe are trying to make sure that our wheat and barley is protected from these new stem rusts that are emerging,âÄù Garvin said. Garvin, who is also employed by the United States Department of Agriculture , said his research is directed toward the United States. However, he said whatever comes of the research can be spread throughout the world. âÄúThis is an international concern,âÄù Garvin said. âÄúWe hope what we learn here can be used elsewhere in the world as well.âÄù Other then stem rust, Garvin is also looking at other diseases. Fusarium head blight is also a fungus-caused disease, and it affects wheat spikes, which house the seeds of the wheat crop, and renders it dead. Fusarium head blight has posed problems in making the wheat resistant through breeding, according to Garvin, who said the disease has been a problem in the Midwest since 1993. Using Brachypodium, Garvin said they can look for a gene in the model plant that increases resistance to Fusarium head blight, and if found, they can look for that same gene in wheat. âÄúWith Brachypodium, we can understand the process, and then quickly test its relevance in wheat,âÄù Garvin said. One method used by Garvin to identify these kinds of genes is by chemically creating mutated genes in Brachypodium. Garvin said the plantâÄôs ability to resist diseases like stem rust is then measured. Regardless of if the plant is more or less resistant, the mutated genes are identified. âÄúIt provides us insight into genes that are playing a role in conferring resistance,âÄù Garvin said. However, finding genes of resistance through mutations is not a quick process, according to Anastasiya Lavell, junior in biochemistry. Lavell, who does a lot of the planting for Garvin, said once the seeds are planted and grown, the thousands of Brachypodium are gone through to find the ones that are truly mutated. The group then looks for characteristics pertaining to resistance, according to Lavell, who said multiple generations of progeny are still required to confirm the characteristics. Lavell said of the thousands of plants they have screened, only a few mutants affected resistance. âÄúAt times it can kind of seem like a dead end, but it is very exciting to see one with the potential to be valuable,âÄù Lavell said. The research Garvin and Lavell are doing with Brachypodium would not be possible without the International Brachypodium Intiative, which is an international collaboration to identify the genes in the model plant. Todd Mockler, Ph.D., assistant professor in botany and plant biology at Oregon State University , said the project identifies the genes responsible for traits like how tall a plant is, its drought tolerance and disease resistance. Mockler, who also worked on the initiative, said before it, Garvin would have to look at 25,000 genes, where now he looks at only about a 100 genes. âÄúIt makes it a plausible number to realistically study,âÄù Mockler said. With the initiativeâÄôs work, Mockler predicts the upcoming years will bring a number of breakthroughs in numerous fields, including biofuels and foods. âÄúThere is going to be a tremendous acceleration in the pace of discoveries,âÄù Mockler said. For Garvin, his discoveries may have the potential to save lives by protecting the global food supply. âÄúWe want security basically,âÄù Garvin said. âÄúWe want to make sure we are trying to develop tools to insure that outcome.âÄù