What are Alternaria Sex Genes Up to, If not Sex?
Fungal diseases are among the most intractable problems faced by farmers. Treatments are few and far between and are often highly toxic. What to do when faced with a fundamental problem with no obvious solution? Scientists at Washington State University are taking a step back to get a bigger view.
The fungal conundrum under examination by WSU plant pathologists has a name: Alternaria, a genus of asexual fungi with around 300 species. Alternaria species cause leaf spot diseases of potatoes and Brassica seed crops in Washington and diseases and decay of many other plants around the world. This fungus is also known to cause respiratory allergies in humans. But it wasn’t the devastation caused by the fungus that brought Alternaria to the attention of plant pathology graduate student Jane Stewart and her advisor, Tobin Peever, an associate professor in the WSU Department of Plant Pathology. They were interested in this question: Why does an organism only known to reproduce asexually have active sex genes?
Studies in another type of fungus had suggested a link between sex genes and the ability of the organism to cause a disease. Could this be the case in Alternaria, as well? By looking carefully at molecular patterns in the genes themselves, Stewart discovered that Alternaria‘s sex genes are under strong selection pressure to maintain function despite the fact that the genes are not required for sex. Previous research by scientists in Japan had demonstrated that sex genes were expressed and likely produced proteins. These sex proteins, Stewart proposed, may play a role in the fungus other than for reproduction. Supporting this hypothesis, Stewart demonstrated that disabling the function of one of the sex genes reduced the virulence of Alternaria on cabbage. The results of Stewart’s research were published in the journal PLoS One.
“Understanding the mechanisms underlying the evolution of plant pathogens will enable us to predict host shifts and understand the mechanisms controlling virulence in plant-pathogenic fungi,” said Stewart. This basic research on the evolution of sex genes in asexual fungi may help us one day understand how fungi and plants interact and allow us to modify this interaction to benefit agriculture.
After graduating with her Ph.D., Stewart took a position as a post-doctoral fellow at the USDA-Agricultural Research Service’s Horticultural Crops Research Laboratory in Corvallis, Oregon.
To learn more about plant pathology research at WSU, please visit the Department of Plant Pathology website at http://plantpath.wsu.edu/. The paper by Stewart et alia is available online via PLoS One’s web site: http://bit.ly/yc9vur.
WSU Plant Pathologist’s On-line Powdery Mildew Database Selected as Standard Reference for Professional
For the past decade, WSU plant pathologist Dean Glawe has been painstakingly compiling information on the world’s Erysiphales fungi. Farmers and gardeners the world over know Erysiphales as the cause of powdery mildew, among the world’s most damaging plant diseases. Powdery mildews attack apples, cherries, grapes, hops, wheat, onions, strawberries, gourds, melons, and many other economically important crops. Growers spend millions of dollars annually trying to control them, applying more fungicides to control powdery mildews than any other plant pathogen.
Devising effective, environmentally safe, and sustainable tactics for controlling powdery mildews is hampered by the fact that there are nearly 700 species that vary tremendously in their life cycles, the plant species they attack, and their capacity to cause damage. In order to provide diagnosticians and researchers with better tools to identify these fungi, Glawe led the development of the web-based Erysiphales Database. The database enables users to identify powdery mildews and to find information on their host plants, and it provides links to online scientific references.
The American Phytopathological Society, the world’s largest professional society of plant pathologists, recently chose Glawe’s database as a standard reference for authors submitting papers on powdery mildews to the journal Plant Disease. “Recognition of this database by the American Phytopathological Society is a testament to Dr. Glawe’s stature and reputation as a leading expert on this economically important group of fungi,” said Hanu Pappu, professor and chair of the WSU Department of Plant Pathology.
Glawe, a professor in the WSU Department of Plant Pathology, is well known for his research on powdery mildews. The Erysiphales Database represents his third foray into producing online mycological resources. Previously he developed the web-based Pacific Northwest Fungi Database with the goal of providing information on plant-associated fungi in the region. He also served as founding editor of North American Fungi, the world’s first online mycology journal.
The databases, as well as North American Fungi, are free and publicly available. The Erysiphales Database is online at http://erysiphales.wsu.edu/. The Pacific Northwest Fungi Database is online at http://pnwfungi.wsu.edu/programs/aboutDatabase.asp. North American Fungi is online at http://www.pnwfungi.org/.
Export Assistance Program
New-to-export and new-to-market firms with little or no expertise in international trade may want to consider consulting with WSU’s Export Assistance Program. The Export Assistance Program’s goal is to create a “culture of exporting” across the state and seeks to support embryonic export relationships, which can develop into long term partnerships. Research shows that firms located near exporters have a greater likelihood of exporting to those same destinations than otherwise. By creating a culture of exporting in Washington, the program’s team members hope to start a cascade effect, where exporting grows from one firm to another.
The Export Assistance Program provides:
- no-cost confidential, in-depth, and long-term one-on-one export advice;
- assistance in preparing market and trade research and understanding export and exchange rate data;
- assessment of the client’s export readiness;
- collaboration with the client to develop a plan that ensures short and long-term exporting success;
- guidance in navigating international trade forms and paperwork; and
- additional resources as needed.
The Export Assistance Program at the School of Economic Science specializes in assisting agricultural producers. Its service is provided by Dr. Andrew Cassey and Dr. Yunfei (Eric) Zhao. They have research expertise and industry experience in international trade, plus many years of living and working abroad.In additional to experts in the School of Economic Sciences, the Export Assistance Program at the Small Business Development Center has four international trade specialists. Further, clients have access to 24 small business development centers statewide and 26 certified business advisors.
If you are considering becoming an exporter, and would like no-cost assistance, please contact Yunfei (Eric) Zhao at firstname.lastname@example.org.
Cook Farm Named USDA Long-term Agroecosystem Research Site
WSU’s R. J. Cook Agronomy Farm in Pullman has been named one of just ten long-term agroecosystem research sites in the country by the U.S. Department of Agriculture.
“This designation is testimony to the quality of work being conducted by ARS and WSU to make agriculture more sustainable on all fronts,” said Rich Koenig, chair of WSU’s Department of Crop and Soil Sciences
The USDA Agricultural Research Service designated the ten sites specifically to engage in research addressing questions related to the condition, trends and sustainability of agricultural systems and resources across the United States. According to the ARS, sustainable agricultural systems that provide a safe, nutritious, ample and reliable food supply; produce bioenergy; provide essential ecosystems services; and mitigate climate change are needed for the well-being and welfare of future generations, according to the ARS.
The ARS Land Management and Water Conservation Research Unit in Pullman will coordinate the Cook Farm LARS. David Huggins, WSU adjunct soil scientist and USDA-ARS soil scientist, will be the principal investigator for the site. Cook Farm was established by a team of ARS and Washington State University scientists involved in direct-seed cropping and precision agricultural research.
Enhanced resources in the ARS Initiative on Environmental Stewardship requested in the fiscal year 2013 President’s Budget will strengthen the capacity of ARS to conduct network-wide research in diverse agricultural systems across the country. Environmental data collected from this network will enable integration and synthesis of findings with the Long Term Ecosystems Research network and the National Ecological Observatory Network sponsored by the National Science Foundation.