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"Of the soil samples processed at
the clinics, more than 75 percent were positive for
SCN," Kirby says. "At least 80 percent of those
positive samples were well above the economic
threshold." This trend is especially disturbing because early detection of SCN plays a key role in long-term management of this pest. Some fields had more than 50 cysts per 100 cc of soil, which is a population level that will take several years of careful management to adequately reduce. "Many farmers expressed surprise at the levels of SCN in their soil samples because this pest often is thought of only as a problem in the lighter soils of the southern parts of the state," Kirby says. |
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| One reason that the SCN populations can
increase so readily in the heavier soils of central and
northern Illinois is that those soils are more supportive
of plant growth, even in years with environmental
stresses. "Although SCN may be present in the soil, plants often do not exhibit the typical above-ground symptoms seen with lighter soils," Kirby says. "The only symptom may be a reduction in yields. Thus, SCN can increase in these soils without any visual detection by producers." He warns, however, that as few as four years of growing a continuous resistant soybean can produce a nematode race shift that will leave a field with populations that cannot be managed by resistant varieties. "SCN can be successfully managed through an integrated approach that includes sampling, proper variety selection, and crop rotation," Kirby says. "However, waiting until plants seem to be injured and yields have declined may mean a lot more time invested in managing this soybean pest." One major problem in developing improved resistant varieties for SCN is that the test currently used to identify different races is labor intensive and requires large greenhouse facilities. The test also takes a minimum of one month to complete and does not provide exact information on the genetics of the different races. With support from the Illinois Soybean Checkoff Board, Greg Noel, nematologist with the USDA's Agricultural Research Service and the U of I's Department of Crop Sciences, has been working to develop a test based on genetic markers that could overcome many of the difficulties in identifying SCN races. "In most cases, the resistance to SCN in soybean cultivars is race specific," Noel says. "Unfortunately, because SCN is genetically highly variable, even this resistance is not durable." The two most commonly used sources of resistance for varieties grown in Illinois are the Peking and P188.788 germplasms. One notable exception is the cultivar Hartwig, which is highly resistant to all SCN populations with which it has been challenged. Nevertheless, this variety is susceptible to brown stem rot and Phytophthora root rot. Several breeding programs, however, are attempting to move the high level of SCN resistance from Hartwig to agronomically superior cultivars. As breeders continue to work on this problem, one approach that seems to show real potential for growers is rotating cultivars with different combinations of race resistance. If the specific races in a field can be readily identified, a sequence of different sources of resistance could be tailored to prevent the buildup of SCN populations above the damaging threshold in standard rotations. "Our data from long-term field studies indicate that rotating resistance genes from different sources and knowing the expected reaction of a specific SCN population will prolong the effective longevity of cultivars having different sources of resistance," Noel said. "One key to making this system work is the development of an improved test for identifying the races." To date, Noel and molecular virologist Les Domier have examined three different techniques that use genetic markers to identify differences among races of SCN. Testing by random amplified polymorphic DNA (RAPD) and restriction length polymorphism (RFLP) of PCR-amplified ribosomal DNA both proved only partially successful. However, early tests of a new technique known as amplified fragment length polymorphism (AFLP) analysis show real promise. "Using just two AFLP primer combinations, we have been able to identify markers unique to the populations of SCN and to several closely related species," Noel says. "In our studies on host resistance, AFLP analysis has generated a large number of genetic differences between SCN races and shows very reproducible banding patterns." These initial experiments produced significant genetic differences in approximately 28 percent of the bands observed among races 1, 3-5, and 14. According to Noel, that level of genetic difference, coupled with an analysis of multiple independent samples of each race, should be enough to identify specific markers for different races. "Identification of races within a field or even a larger area could take place in a single laboratory in only days rather than weeks," Noel says. "Detailed genetic information from such a testing program could greatly assist breeders in developing improved resistant cultivars and could allow growers to extend the effectiveness of resistant varieties currently on the market." |
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A major research project underway at the
University of Illinois is focusing on development of new
strategies that will help the soybean industry compete
effectively well into the 21st Century. The project,
titled "Crafting Future Strategic Visions for
Illinois Agriculture," also encompasses development
of similar strategies for the corn, cattle, and swine
industries. The intent is to work with firms representing points all along the value chain in each area to develop a vision of where they want their industry to be in the future and how to get there," |
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| says Randy Westgren, project co-leader
and associate professor in the U of I's Department of
Agricultural and Consumer Economics Steve Sonka, director of the National Soybean Research Laboratory (NSRL), serves as the other co-leader of the project. The project relates directly to Sonka's role as holder of the Soybean Industry Chair in Agricultural Strategy in the U of I's College of Agricultural, Consumer and Environmental Sciences. It also builds on earlier work by Westgren on the competitiveness of Illinois agricultural industries, which was developed under a grant from the Illinois Council for Food and Agricultural Research (C-FAR). Westgren notes that the project is especially timely because the food and agricultural sector is experiencing unprecedented pressures for change. Consumers and customers increasingly are becoming more demanding even as rivals in global markets are raising the competitive stakes. "As the trend toward reduced federal farm income support levels increases producer risk, new market linkages are emerging between producers and their customers," Westgren says. "Society further is demanding higher levels of accountability from agricultural production and marketing systems, especially with respect to food safety and environmental concerns." At the same time, according to Westgren, access to more sophisticated technologies in both the biological and information areas offers new opportunities to respond to the marketplace and to societal challenges. "These, and other existing pressures, make it imperative that agricultural leaders acquire the capabilities to respond strategically," he says. "Increasingly agricultural managers need to be able to create and evaluate options that extend beyond the boundaries of the individual business, trade organization, or farming operation." As part of the project, six international experts in strategic visioning came come together at the NSRL to review project methods. This group included Rhonda Reger of the University of Maryland, Ari Ginsberg of New York University, Erik Larsen of the University of Bologna, Peter Grinyer of the University of St. Andrews, Paul Raimond of the City University of London, and Joseph Porac of the U of I's College of Commerce. "Getting these people, who are known for their experience in organizing such studies, to come together here was an extraordinary achievement on its own," Westgren says. "We posed to them how we propose to execute the research and gained their insights based on extensive experience doing these sorts of projects with individual firms." For each industry, the U of I team will bring together representatives for facilitated group workshops focused on strategic visioning. The workshops will be complimented by individual interviews with managers throughout the value chain. Detailed information relating to markets, trade, and other factors will be assembled for each of the four agricultural industries. Participants in the Illinois Soybean Leadership Program of the Illinois Soybean Association served as one of the first test groups for the research protocols. About a dozen of the leaders participated in sessions at the NSRL with Westgren, Sonka, and Peter Foreman of the U of I's College of Business Administration on developing a vision for the soybean industry. "What we got from them was a real breakthrough in thinking about the future issues in their industry," Westgren says. "As we move along, we will add to this base of information by getting additional groups from the soybean industry to participate in the process of strategic issue identification." As a result of this and other sessions, the U of I team will construct computer models incorporating all the gathered information. These computer models will allow managers to simulate alternative future directions for their industry. "These models will help build explicit pathways into the future that will assist each industry in building its own strategic vision," Westgren says. "What this whole process is all about is not letting the future just happen to us, but instead creating the future we want." As the final part of the process, another round of workshops will be held to examine the "What-ifs?" facing each industry. The results of the project are expected to be available in 1998. Westgren emphasizes that this is not a reactive project. Instead, it represents an attempt to stay ahead of the coming changes in the soybean industry. "We're attempting to help the soybean industry identify the challenges and changes it faces and craft strategies for successfully dealing with the future," he says. "We don't believe that the future of the soybean industry is already determined. We believe that producers, processors, and others in the industry can help determine the future." Researcher
Presents New Approaches For Analysis Of
The Soybean Genome Modern recombinant DNA technologies can be used not only to clone individual genes, but also to study the organization and evolution of entire genomes. These methods have been used to reveal a vast array of genes for disease resistance within the soybean genome. They also are illuminating how the ancient tetraploid nature of the soybean genome, in which a key ancestor of the modern soybean underwent a doubling in chromosome numbers, affects gene segregation and evolution. These and other important topics concerning the study and manipulation of the soybean genome served as the focus for a recent presentation in the NSRL Seminar Series by Randy Shoemaker, research scientist with the USDA's Agricultural Research Service and professor of genetics in the Department of Agronomy at Iowa State University. The event was co-sponsored by several departments at the University of Illinois. Shoemaker is widely acknowledged as a leader in molecular genetic analysis and manipulation of the soybean genome. As part of his visit, he met with scientists at the NSRL and other units of the U of I, with special emphasis on interactions with graduate students and other young trainees. During his seminar presentation, Shoemaker noted that, as a result of the doubling in chromosome number, many genes in soybean are present in four copies instead of the usual two and that these genes reside on different chromosomes. While soybeans generally are considered to behave as diploid plants, the ancient tetraploid origins of the genome have altered gene segregation in ways that are only starting to be understood. "What is especially important is that Shoemaker and his colleagues have helped define the extent of tetraploid as opposed to diploid behavior and the effects that these differences can have on soybean genetics and molecular biology," says Andrew Bent, assistant professor of molecular genetics in the U of I's Department of Crop Sciences and coordinator for Shoemaker's visit. Shoemaker also has pioneered the development of recombinant DNA tools for the improvement of soybean varieties. Marker-assisted selection, for example, is an actively growing branch of plant breeding that utilizes DNA markers to track the segregation of specific chromosome segments. "His laboratory has played a key role in the development of DNA markers, such as restriction fragment length polymorphism (RFLP) markers," Bent says. "More importantly, he has guided the organization of these markers into coherent molecular genetic maps of the soybean genome. He also is involved in collaborative efforts to develop and map PCR-based markers that are cheaper and easier to use than RFLP markers." Shoemaker's work has included development of a computer database for these markers and maps. This USDA-sponsored database, known as Soybase, provides geneticists and breeders with easy access to data from many laboratories, as well as from the literature and other databases. Soybase can be accessed at http://probe.nalusda.gov:8300/cgi-bin/browse/soybase. It also can be found at http://www.ag.uiuc.edu/-stratsoy/new/ on the U of I's StratSoy system. "DNA markers also can be used to help isolate important plant genes based on their location on a chromosome," Bent says. "This technology is very challenging to implement for plants with large genomes such as the soybean, but Shoemaker is working to make these approaches possible." For this approach, it is necessary to have libraries of DNA clones containing small segments of the genome. During his visit, Shoemaker discussed successes in generating gene libraries for soybean using yeast artificial chromosome (YAC) and bacterial artificial chromosome (BAC) cloning vectors. As part of his seminar, he devoted attention to recent success in isolating disease resistance gene analogs from soybean. In the last few years, genes that confer resistance against various fungal, bacterial, and viral diseases have been isolated from a number of other plant species. Researchers have identified regions of similarity between many of these disease resistance genes. "Shoemaker's group used these conserved sequence signatures as a tool to directly isolate soybean genes containing the conserved regions," Bent says. "They have isolated a tremendous number of these genes, which should serve as a valuable resource in future engineering for improved disease resistance." From the Director's Desk As I commented recently to an undergraduate class of mine, today's agriculture graduates simultaneously face the most promising opportunities and the most daunting challenges that I've seen during my 25 years in the profession. |
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Both the opportunities and
challenges are deeply intertwined with three global
trends: the potential for significant growth in global
demand fueled by income and population increases around
the world, the advent of technological innovations that
could allow us to better deal with market and
environmental changes, and the loosening of international
trade constraints across the globe. Although these trends offer considerable promise, that potential is far from assured. |
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| As renowned management expert Peter
Drucker stresses--"the future is not going to be
made tomorrow; it is being made today." Research, of course, is all about creating the future through actions that we take today. At the National Soybean Research Laboratory, we are surrounded by dedicated scientists and students committed to improving the soybean industry through their research and scholarship. This issue of the Bulletin presents several examples of these activities. I believe that one item highlighted in this issue--the project on crafting future strategic visions for Illinois agriculture--is especially noteworthy. Under the leadership of Professor Randy Westgren of the Department of Agricultural and Consumer Economics, the project promises to be a critically important focus for the NSRL during the remainder of this decade. This effort is filled with both excitement and challenge. As the three global trends noted above have accelerated the pace and complexity of change, the soybean industry is faced with the need to respond more effectively within this turbulent environment. That response certainly must include further evolution of our research and development systems to better meet the challenges presented by complex and rapidly changing market environments. A key outcome of the project on crafting future strategic visions will be development of tools and procedures that will enable decision makers in the soybean industry to better respond to future complexities and uncertainties. Undoubtedly the evolution of this project will include developing better mechanisms to anticipate tomorrow's needs and to transmit those needs throughout the soybean production and marketing system. Although only one step, it is my fervent belief that the project on crafting future strategic visions can play a key role in accelerating the evolution of the soybean research and development system to better meet the global challenges that we all confront today. Steven Sonka New
NSRL Publications Available Two new books in the NSRL publication series, Guidelines for the Integrated Management of Soybean Pests and Major World Soybean Diseases, Weeds, and Insect Pests: A Pictorial Atlas, are now available to the public. The 48-page guidelines volume, written by James B. Sinclair and Marshal McGlammery of the University of Illinois and Marcos Kogan of Oregon State University, provides detailed information on integrated pest management (IPM) for the major pests of soybean worldwide. It also presents background information on both applied and theoretical approaches to IPM systems for arthropods, diseases, and weeds. The publication will assist soybean producers not only to understand the role of IPM, but also will help them in implementing such programs. The text includes more than 130 high-quality color illustrations. The 24-page atlas, written by Marcos Kogan, Michael Irwin, James B. Sinclair, and Fred Slife, features more than 130 color illustrations, many of which provide an approximation of the shape and color of the major arthropods species affecting the soybean. A number of plates are enlarged to show details. Accompanying silhouettes are drawn to scale and indicate natural size. A table of contents lists the common names of the various illustrated pests for easy reference. Both publications are suitable for use as an aid in classroom and outreach activities, as well as for crop consultants and growers. Single copies of the two books are available free of charge, including no cost for shipping, upon request to: Publication Sales, OAF, UIUC, 69 Mumford Hall, 1301 W. Gregory Drive, Urbana, Il 61801. Information on the cost for multiple copies is available by calling (217)333-2007. Presented by College of Agriculture University of Illinois at Urbana-Champaign National Soybean Research Laboratory 170 National Soybean Research Center 1101 West Peabody Drive Urbana, IL 61801-4723
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