Developing a Wheat Safe for Celiac Disease Patients
Thanks to the research of Diter von Wettstein and a grant of nearly $1 million from the National Institutes of Health, millions of people around the world suffering from celiac disease have new reasons for hope.
Von Wettstein, who is R.A. Nilan Distinguished Professor in the Department of Crop and Soil Sciences and the School of Molecular Biosciences at WSU, is using the NSF grant to advance his research to develop wheat varieties safe to eat by people with celiac disease.
Celiac disease is a genetic digestive disease and autoimmune disorder that damages the small intestine and interferes with absorption of nutrients from food. Symptoms range from cramps and diarrhea to malnutrition and other serious illnesses, such as diabetes. The disease is triggered by consumption of the gluten proteins found in wheat, barley, and rye.
Currently, the only treatment is a gluten-free diet, eliminating all wheat, rye, and barley-based foods. Making such a diet more difficult, gluten is used as a filler or binder in many food and non-food items, such as deli meats, licorice, medicines, vitamins, and even the adhesive on stamps and envelopes.
“Medical experts at the National Institutes of Health have declared urgency in dealing with celiac disease, the most common food-sensitive intestinal condition in humans. We require faster and more decisive methods such as transgenic breeding, in which genes are transferred from different species, and non-transgenic TILLING (Targeting Induced Local Lesions In Genomes),” von Wettstein said.
Von Wettstein, a member of the National Academy of Sciences, and his team have discovered a fully viable, lysine-rich barley mutant that lacks proteins that trigger celiac disease. But this barley mutant retains high-molecular-weight glutenins, recently shown to be solely responsible for dough elasticity and excellent baking quality. The task for von Wettstein is to produce a similar wheat grain, using genetic methods to remove the celiac-causing proteins and low-molecular glutenins. As an added benefit, the resulting grain will contain more lysine, an amino acid essential for an optimal diet but typically deficient in wheat.
The research team has partnered with Seattle-based biotechnology company Arcadia Biosciences to screen large populations of wheat mutants by TILLING, in order to identify gene mutations that affect the celiac-triggering protein types.
High Tunnels Extend West Side Growing Season for High-value Crops
Washington State University Mount Vernon researchers are exploring the use of high tunnels to help Washington growers earn a higher return on their crops. High tunnels can increase fruit production, improve crop quality, extend the growing season, and reduce disease.
“We want to help growers on the west side get more return per acre by using high tunnels,” said Tom Walters, small fruit horticulturist. Walters is a member of the high-tunnel research team at the WSU Mount Vernon Northwestern Washington Research and Extension Center.
In its second year, the project, funded in part by a U.S. Department of Agriculture specialty crop planning grant, is analyzing the adaptation and economic feasibility of using high tunnels in the cool marine climate of the Pacific Northwest.
The researchers are measuring the growth of tomatoes, strawberries, lettuce and potatoes inside the tunnels versus outside the tunnels to determine if particular varieties are better suited to tunnel production in western Washington. The tunnel influences environmental and pest factors, which will in turn influence variety productivity and suitability for tunnel production, according to Carol Miles, Extension vegetable specialist and research team member.
A high tunnel resembles a plastic-covered greenhouse, but is a non-permanent structure. Also, high tunnels have no automated heating or ventilation and are covered with a single layer of 6-mil thick plastic.
The researchers are exploring high tunnels as a method for controlling disease in some organically produced crops.
“There can be few effective organic control options for some diseases on some crops,” Miles said. “Growing a disease-free crop can be easier with high tunnels.”
High tunnels increase daytime temperatures and keep rain off the crops. Crops can be started earlier in the season and quality is improved because some disease problems are reduced. Warmer temperatures and shelter from rain also mean that plant leaves dry faster.
“Although leaf wetness looks like it may play an important role, we do not know for sure what causes the reduction of these diseases in the tunnels,” said Walters.
“In western Washington, so far, we have found late blight on tomatoes and Botrytis blight on strawberries to be reduced in high tunnel settings,” said Debra Inglis, a plant pathologist and member of the research team.
Another issue tackled by the researchers is consistency of quality, which is often a problem with strawberries. Under a high tunnel, the strawberry plants produce the same quality week after week. The season starts about a week earlier and extends a little bit longer than usual.
With lettuce, as well, the high tunnels extend the growing season at both ends. Lettuce could be grown year round in a high tunnel, but the structure needs to be taken down because of wind and snowfall during the winter in western Washington.
Miles and Walters are doing intercropping research by planting lettuce and strawberries in the beds at the same time.
“Tunnels are expensive, so we want to see if we can enhance their productivity by growing lettuce between the strawberry plants,” Walters said.
In the intercropping system, strawberries are the primary crop and growers do not want to reduce their yield. At the same time, when strawberries are first planted they are quite small, so if the space between plants can be used to grow a fast crop, such as lettuce, growers can gain from marketing this secondary crop with essentially no additional expenses.
by Holly Luka, Marketing, News, and Educational Communications intern