Guarding against bioterrorism and accidentally introduced pests and pathogens, the Northeast Plant Diagnostic Network, headquartered at Cornell, is fulfilling the university's land-grant mission in the 21st century.

 

Patho Genie: Plant samples await scrutiny by Karen Snover-Clift '97, MPS '98.

It may have been hard to imagine more than a century ago that Cornell's land-grant mission would eventually mean playing a central role in national agricultural security. Today, the reality of protecting agriculture and food security in the 21st century includes detecting either accidentally or deliberately introduced pests and pathogens and guarding against potential acts of bioterrorism.

This is in addition to the college's traditional role in monitoring and eradicating traditional plant pests-weeds, insects, and diseases-to combat extensive annual yield losses to crops. The economic impact of exotic pests or pathogens would not only reduce crop yields, but also would affect the marketability of crops themselves. Cornell's land-grant status charges it with protecting and advancing agriculture in the United States in general and in New York State in particular.

Taking on this challenging package of responsibilities is the Department of Plant Pathology in the College of Agriculture and Life Sciences, with its more than 30-year history of diagnosing plant diseases through its Plant Disease Diagnostic Clinic. That clinic is now the centerpiece of the Northeast Plant Diagnostic Network (NEPDN), which is part of the even larger National Plant Diagnostic Network. As one of the network's regional centers, Cornell has been selected by the U.S. Department of Agriculture and the U.S. Office of Homeland Security to coordinate an advanced surveillance and detection program through the network. This program, which was established in 2002, has taken existing facilities within the country's land-grant university system and supplemented them with funding for improved communication equipment, software development, and identification technologies.

This coordinated network's mission is to enhance national agricultural security by quickly detecting any introduced pests and pathogens and then to quickly report findings to the appropriate responders and decision makers.

"The diagnostic network and our clinic is an integral part of Cornell's land-grant mission and provides a real service to agriculture, because more and more, our agricultural producers are functioning in a world economy," says Rosemary Loria, plant pathology professor and department chair. "That means there are many, many possibilities for introducing new plant diseases, new insect or weed pests, into agricultural systems. The introduction can be accidental, or in the case of bioterrorism, it can be purposeful. But in either case, it's critical that we have the ability to detect introductions, to quickly assess the implications of an introduction, and communicate the need for mitigation."

Last summer, Cornell's Plant Disease Diagnostic Clinic was given one of its first big assignments as part of the NEPDN: following an outbreak of plum pox in Pennsylvania in 1999 and in Canada in 2000, an extensive survey of New York orchards was needed to determine whether the viral disease had migrated to any of the state's crops or whether efforts to contain it in the orchards where it had been found were successful in eradicating it. Plum pox is one of the organisms on the Agricultural Bioterrorism Act's Select Agent list.

Pennsylvania invested more than $5.1 million to eradicate the plum pox virus and indemnify farmers for the destruction of infected trees; the USDA allocated $4.7 million to the containment effort; and federal agencies approved a minimum of $18.5 million to compensate for losses due to plum pox.

Plum pox, which is also known as sharka, affects stone fruit trees such as plum, peach, and apricot and has devastated crops in Europe for a century. It is transmitted over short distances by aphids.

Nearly 15,000 samples, sent in from stone fruit orchards all over New York State, were tested at the Cornell clinic last summer. No trace of plum pox was found. Testing of samples from New York orchards is expected again this year, since symptoms of the virus occur sporadically, sometimes not even appearing until up to three years after the initial infection. Laboratory tests can detect the virus before visible symptoms are apparent.

Diagnosticians at the clinic are also keeping a careful watch on a new outbreak of a geranium blight disease that appeared in four greenhouses in the Midwest last year after coming from geranium cuttings imported from Kenya. The four greenhouses were rooting stations that produce plants for thousands of wholesale and retail greenhouses The January to May 2003 event put 921 greenhouses on hold in 47 states and resulted in the destruction of 2 million plants in 127 facilities.

While the bacterium, known as Ralstonia solanacearum, can usually be kept isolated because geraniums are largely a greenhouse crop, it could pose a significant threat to other crops, like potatoes, if it spread outside the greenhouse. This disease, which causes plants to wilt, yellow, and die, is found globally, except in the United States and Canada. It is one of the 10 threat pathogens the USDA has designated as particularly dangerous to U.S. agriculture.

The five regional laboratories are being equipped with state-of-the-art equipment and supplies needed to perform DNA-based diagnostic analyses for bioterrorism threat pathogens that the network deems important. This spring, representatives from the five labs received training on three select agent pathogens and one pathogen of high significance. The pathogens are Phakopsora pachyrhizi and P. meibomiae, the causal agents of soybean rust; Ralstonia solanacearum R3 B2, the causal agent of southern wilt of geranium and brown rot of potato; plum pox virus, the causal agent of plum pox; and Phytophthora ramorum, the causal agent of sudden oak death.

Cornell's position as the center of the NEPDN includes a mission of educating diagnosticians throughout the national network on proper testing protocol and procedures. "A lot of the educational information we're going to be putting together as a national network will be geared toward a group of people that we're labeling as 'first detectors,'" says Karen Snover-Clift, a senior extension associate and plant disease diagnostician who is also the assistant director of the NEPDN. "These educational packages will show how to collect a good sample, how to look for abnormalities and know that something should be submitted, and how to get that into the network so it can be analyzed."

First detectors include growers, crop consultants, pesticide applicators, master gardeners, commercial chemical and seed representatives, and Cooperative Extension personnel. A Web-based diagnostic system will be used to report unusual pest occurrences, existing crop conditions, and other information that would not normally be submitted through the diagnostic network.

Cornell is also one of two universities that will house the servers and that are part of a pilot program testing an advanced Plant Disease Identification System (PDIS) software package that will eventually be used by 29 states.

- Joe Wilensky

In 1862, Congress passed the Morrill Act, granting each state in the union 30,000 acres of federal land for every member of its congressional delegation. The states then sold the land to finance colleges that would provide education in practical areas such as agriculture and engineering. These institutions were further mandated to use the knowledge generated in these disciplines for the public good. Cornell was chosen to be the land-grant college for New York.

Today, the College of Agriculture and Life Sciences meets its land-grant responsibilities through research, teaching, and extension efforts that make an important difference in the lives of our stakeholders.

These include:

• Providing a world-class education for our students
• Encouraging lifelong learning through extension education
• Advancing a productive and sustainable agriculture
• Understanding the unity and the diversity of life through discovery in the life sciences
• Promoting wise stewardship of the environment
• Supporting a safe, secure food supply
• Fostering economic vitality
• Facilitating individual and community health and well-being
• Pursuing scholarship that addresses social issues

Here are some examples of how the college is fulfilling its land-grant mission:

• Farmers, gardeners, schoolchildren, and golfers can thank the New York State Integrated Pest Management program (IPM) for developing pest management tools that are cost effective and minimally impact the environment and human health. The program has grown since its inception in 1984. Today there is an IPM team for each commodity.
• The grape and wine industry in New York is expanding rapidly, but growth is hindered by a shortage of qualified enologists and viticulturists. A new concentration in Viticulture and Enology within the Plant Sciences and Food Science majors will give graduates the skills for successful careers in the wine industry, including expertise in grape growing, wine making, business management, and marketing.
• What do food companies in New York do when they need help with developing new products or solving problems with old ones? They turn to the college's Food Venture Center at the Geneva experiment station. There they receive guidance and expertise in food safety issues, government regulations, sensory evaluation, product development, and resource networking.
• Managed by personnel in the college's Department of Animal Science, PRO-DAIRY is an educational program that increases the profitability and competitiveness of New York's dairy industry. The program enables agricultural producers to achieve their professional and personal goals by providing education in dairy facilities engineering, farm business management, and human resource management.
• Researchers in the Department of Horticulture have developed methods of producing fresh raspberries using greenhouses that might otherwise sit empty during the winter. Growers in New York, the Northeast, and the Midwest have begun commercial production of winter raspberries, meeting strong demand and capitalizing on off-season prices.