Banking on Local Greens
It’s the frustration of every gardener in the Inland Northwest and other northern parts of the country: You plant lettuce as soon as you can work the soil in the spring, but the temperature takes a dive, and instead of providing an early harvest, your seeds rot in the ground.
Although lettuce is a cool-season crop, current varieties won’t germinate if it gets too cold. According to Gardening in the Inland Northwest by Tonie Fitzgerald of WSU Extension’s Master Gardener program, lettuce will germinate at soil temperatures as low as 35 degrees Fahrenheit, but the optimal soil temperature is a much higher 75 degrees. If the germination temperature could be pushed downward, both gardeners and commercial growers could plant early with confidence
But how to train lettuce seeds to germinate at lower temperatures? Carol Miles, a vegetable horticulture specialist at the WSU Mount Vernon Northwestern Washington Research and Extension Center (NWREC), suspects there are lettuce lines unknown to commercial breeders that can germinate early, and that these traits can be transferred to commercial lettuce varieties for the thrill of anyone who has spaded a frosty garden in April.
To obtain sources of lettuce for testing, Miles decided against traveling to Asia Minor, Iran, and Turkistan where lettuce originates, and scouring mountain drainages and rural gardens for lettuces new to the West. Instead, she took advantage of the 295 different types of lettuce seeds housed at the USDA Western Regional Plant Introduction Station (WRPIS) in Pullman. The station is one of four regional seed repositories in the National Plant Germplasm system.
Miles and her graduate student Charlene Grahn established a climate-controlled growth chamber where they planted lettuce seeds from the seed bank and identified those that germinated at the coldest temperatures. They have just harvested the first season’s crop, and are compiling the results. When the final numbers are in, commercial breeders can choose the most appealing lettuce lines and incorporate the cold-tolerant trait into varieties for commercial growers and gardeners.
“Almost all major crops in the United States–wheat, rice, and soy, for instance–were brought here from somewhere else,” explained Jinguo Hu, research leader of the USDA WRPIS. Imported crops tend to lack genetic diversity, which leaves them vulnerable to challenges such as harmful insects and diseases. “The National Plant Germplasm system was started in 1946 as a way to preserve plant diversity and breeding opportunities for future generations.” The Pullman center has 93,000 accessions, or deposits of seeds collected from a specific place at a specific time. Like all of the regional centers, the WRPIS specializes in specific types of plants. In addition to 2,000 accessions of lettuce, Pullman has over 17,000 accessions of beans, 21,000 accessions of turf and forage grass, 9,000 accessions of forage legumes, and 6,100 accessions of peas.
Historical Success and Current Potential
Hu knows the potential of this collection for lettuce breeding, because he has seen success with other plants. “Early chickpea cultivation was limited in the United States due to problems with Ascochyta blight,” said Hu. But once a specimen was found to be resistant to the causal fungus Ascochyta rabiei, breeders incorporated the resistant gene into the crop, and chickpeas became widely grown again in the West. Peas are also among the success stories, having similarly gained resistance to powdery mildew through selective breeding from the collection.
Miles, serving as the WSU representative to the Western Regional Repository, has a great deal of respect for the value of the repository system. In addition to lettuce research, she and grad student Jesse Wimer are using the collection to find cucurbits (plants in the gourd family) that can be used as disease-resistant rootstock for watermelon grafts. She is also helping Hu find fava bean strains that are cold-tolerant.
The largest impact is likely to come from the lettuce research, however. “Lettuce is the number one vegetable consumed in the United States,” said Miles. “Most of the past seed screening has been to find strains that resist high temperatures. If breeders can develop varieties that grow better at low temperatures, there will be great new opportunities for local food systems.” Instead of eating lettuce shipped thousands of miles from the Sun Belt, northerners might be munching more greens purchased at their local farmers market or harvested in their own backyards.
For more information about the WRPIS, see http://1.usa.gov/1deYiyB. To learn more about vegetable research at WSU Mt. Vernon, see http://bit.ly/wsumtv. To purchase Gardening in the Inland Northwest, go to http://bit.ly/15fG116.
WSU Dairy Club Wins National Knowledge Contest
The WSU Dairy Club took first place among 12 universities at the quiz bowl of the American Dairy Science Association annual meeting recently. This is the first time WSU has won the competition and the second time the trophy will make its way west in the 12-year history of the contest.
“WSU has a core of bright, energetic students who are very interested in the dairy industry,” said Larry Fox, club advisor and professor in the College of Veterinary Medicine and CAHNRS Department of Animal Sciences. “They want to have impact and are willing to work hard to have that impact.
The club provides educational and social experiences for member students interested in any facet of the dairy industry. The quiz bowl is designed to encourage students to learn about dairy science, production, foods, processing, and the American Dairy Science Association.
WSU Dairy Club members prepared for the contest during the school year and even after graduation. Megan Cihak, Kevin Gavin, Danielle Meyers, Brooke Vander Veen, and alternate Jessica Levy swept the final round against Cal Poly 68-20 to achieve the victory. All are animal science majors except for Vander Veen, who recently graduated with a major in agriculture education and a minor in animal science.
Meyers entered veterinary school after her junior year and expects to earn a doctor of veterinary medicine degree. The remaining team members are eligible to compete as the WSU defending champs at next year’s contest in Kansas City, Missouri.
To find out more about the WSU Dairy Club, go to http://www.wsudairyclub.com.