Rick Nelson was born in St. Louis, MO, and grew up in the area. He attended Washington University, obtaining his A.B. degree in biology and psychology in 1978. Nelson became interested in plant research at Washington University through course work and internships at Monsanto. He obtained his M.S. degree in agronomy in 1982 and his Ph.D. degree in biology in 1985 from the University of Illinois under the tutelage of James Harper. His post-doctoral training commenced in the laboratory of Roger Beachy at Washington University, where he was instrumental in showing for the first time that plants could be made resistant to virus challenge through genetic engineering. He became an assistant scientist at the Samuel Roberts Noble Foundation in 1988. Currently, Nelson is a professor at the Noble Foundation and adjunct professor at Oklahoma State University in the Department of Entomology and Plant Pathology. He has authored or coauthored more than 80 scientific papers. Nelson’s research is centered toward understanding virus movement and accumulation throughout the host. He was an early pioneer in recognizing that the host was composed of a diverse array of cell types, each potentially with the unique ability to regulate virus cell-to-cell or vascular movement. He utilized an array of viruses, both native and mutant, to study the determinants in the virus genome for spread and accumulation within the host and the cell boundaries within plants that regulate virus accumulation. His laboratory was the first to study the vascular invasion capacity of a virus, determining that Tobacco mosaic virus (TMV) can enter any vein class in an inoculated leaf to initiate systemic spread. In addition, his laboratory was one of the early pioneers to survey minor vein invasion by different virus genera within hosts displaying different vascular cell morphologies.

Nelson’s laboratory also studied the intracellular activities of TMV. They determined that the TMV replication complex is a dynamic entity that changes its intracellular location and composition as infection progresses. Recently, they were the first to show that both the 126-kDa protein encoded by TMV and the TMV replication complex colocalize with and traffic along microfilaments, suggesting a new model for TMV RNA transport to plasmodesmata. Through collaboration with James Schoelz’s laboratory at the University of Missouri, the P6 protein of Cauliflower mosaic virus, a protein with similarities to the TMV 126-kDa protein, also was found to associate with and traffic along microfilaments. In other work, the Nelson laboratory determined that the ability of a virus expressing a mutant 126-kDa protein with attenuated RNA silencing suppressor activity to systemically infect Nicotiana benthamiana correlates with the absence of an active host RNA-dependent RNA polymerase. This was the first identification in a plant of a natural alteration in a gene associated with RNA silencing and explains the susceptibility of N. benthamiana, a favorite lab “rat” for plant virologists, to tobamovirus hyper-accumulation. Nelson’s laboratory has maintained an interest in viruses that infect monocotyledonous plants. They studied Brome mosaic virus (BMV) infections in barley and determined that 1) virus vascular-centric accumulation is temperature dependent and 2) virus accumulation occurs in guttation fluid and its presence in this fluid is associated with localized cell death within the vascular cells. More recently, the Nelson laboratory with others at the Noble Foundation identified and cloned a strain of BMV that infects rice. The virus was modified to serve as a vector to study host gene function through virus-induced gene silencing for the first time in rice. Nelson has an extensive record as a research collaborator. He has collaborated with Biao Ding, Ohio State University, to study macromolecule intercellular trafficking and the effect of viroids on host gene expression and RNA silencing; Jeanmarie Verchot-Lubicz, Oklahoma State University, to study potexvirus accumulation and movement; C. Michael Deom, University of Georgia, to study virus movement and its determinants; Yi Li, Peking University, to identify a movement protein encoded by Rice dwarf virus; Andy Maule, John Innes Centre, to identify plasmodesmal targeting signals in the Cucumber mosaic virus movement protein; and his former post-doctoral, Ning-Hui Cheng, and Kendal Hirschi, USDA/ARS Children’s Nutrition Research Center, to study the location of proteins involved in calcium flux or oxidative stress response within plants.

Nelson has a long record of professional service both within and outside of APS. He served as vice chair and chair of the APS Virology Committee in 1996–1997. He served as an associate editor for Molecular Plant-Microbe Interactions from 1997 to 1999 and for Phytopathology from 1998 to 1999 and as a senior editor for Phytopathology from 2000 to 2002. Nelson has organized or coorganized multiple APS special sessions. For 15 years, he has been instrumental in securing financial support for APS special sessions sponsored by the Virology Committee. From 1999 to 2003, Nelson served as the APS representative on the American Type Culture Collection (ATCC) Scientific Advisory Council. Outside of APS, he served as an associate editor for Molecular Plant Pathology from 2000 to 2005 and currently is on the Editorial Board for Virology (2005–present). He coorganized or was a member of the organizing committee for multiple international conferences. With Marilyn Roossinck, he coinitiated and, in alternate years, organizes the Noble Foundation Virology Retreat, bringing together approximately 40 researchers from around the world for research presentations and discussion in a relaxed atmosphere (1992–present). Most recently, he helped coorganize a USDA- and Noble Foundation-sponsored DNA marker workshop for breeders and molecular biologists working to improve rice quality and disease resistance (2006). He fulfilled his adjunct professor duties giving guest lectures at Oklahoma State University and as a member of graduate student committees for master’s and Ph.D. candidates. In summary, Nelson is an internationally recognized scientist who has conducted pioneering studies on virus-host interactions. He collaborates successfully with scientists around the world while maintaining an active core research program at the Noble Foundation. In addition to authoring or coauthoring important original research, he has for many years given his time in professional service to APS and other organizations.
 

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Timothy C. Paulitz was born in Erie, PA, and grew up in Montclair, CA. He earned a B.S. degree in botany with a minor in plant pathology from California State Polytechnic University, Pomona in 1979 and a Ph.D. degree in plant pathology from the University of California, Riverside in 1984. He held post-doctoral appointments at Colorado State University from 1984 to 1987 and with the USDA-ARS in Corvallis, OR, from 1987 to 1989. In 1989, he accepted a position in the Department of Plant Science at Macdonald Campus of McGill University, Quebec, Canada, advancing to the rank of associate professor in 1994. In 2000, he joined the USDA-ARS Root Disease and Biological Control Research Unit in Pullman, WA, as a research plant pathologist. Paulitz is recognized as an international leader in research on the ecology, epidemiology, biological control, and cultural management of soilborne fungal pathogens.

At McGill University, Paulitz’s research focused on control of diseases caused by Pythium spp. in hydroponically grown vegetables. His novel screening techniques for biocontrol agents of P. aphanidermatum resulted in the identification of strains of Pseudomonas that were highly effective in increasing the production of cucumbers grown in rockwool. He demonstrated that Pseudomonas spp. suppress Pythium root rot by inducing systemic resistance in the host plant. Paulitz was the first to use a split-root system to spatially separate the pseudomonad and pathogen on cucumber and to demonstrate induced systemic resistance as a mechanism of biocontrol against Pythium root rot. Much of his pioneering work in the area of biocontrol in the greenhouse was summarized in an invited chapter in Annual Review of Phytopathology in 2001.

Paulitz, individually or in collaboration with others, also developed a reliable field inoculation method, identified environmental factors influencing spore release and dispersal, and developed a mathematical model describing disease foci for Fusarium head blight of wheat caused by Fusarium graminearum (perfect stage = Gibberella zeae). He perfected a method of producing epidemics in field plots from laboratory-produced ascospores of G. zeae and was the first to describe detailed spore dispersal gradients and the timing of ascospore release from natural inoculum. His studies have made a major contribution to understanding the epidemiology of G. zeae on wheat.

Soon after joining the USDA-ARS, Paulitz and colleagues at Washington State University discovered that glyphosate applied to resistant wheat and soybean could inhibit stripe rust and soybean rust. Previously, it was thought that fungi were relatively resistant to this widely used herbicide. In 2005, these results were published in PNAS and the technology, which has the potential to be used as a tool for managing the diseases, was licensed to Monsanto.

Paulitz’s current research focuses on root and crown rot diseases of small grains and brassicas caused by Rhizoctonia, Gaeumannomyces, Pythium, and Fusarium. He has elucidated the complex of Pythium and Rhizoctonia species that affect cereal cropping systems in the Pacific Northwest, especially in direct-seed (no-till) systems; described the biogeography of Pythium and Rhizoctonia spp. in eastern Washington; described and characterized previously unknown species and groups of Pythium and Rhizoctonia; and developed novel techniques for screening of cereal germplasm for resistance/tolerance to Rhizoctonia and Pythium. In collaborative studies, he has developed molecular techniques for quantification of 10 Pythium spp. and six groups of Rhizoctonia, technology that has been transferred to industry for commercialization. His research has made huge contributions to small grain producers in the Pacific Northwest through the development of new disease control strategies and new approaches to assess risks from soilborne pathogens prior to seeding. His work has also provided tools for breeders to begin to identify germplasm with resistance or tolerance to Pythium and Rhizoctonia.
Paulitz is recognized worldwide as a leader in the field of biological control and the ecology and management of soilborne pathogens. He is widely sought as a speaker at national and international conferences and has given more than 40 invited symposium or keynote talks at scientific meetings. He routinely conducts collaborative research with scientists in industry and academia. Scientists from all over the world visit his laboratory. He has authored or coauthored more than 90 peer-reviewed publications and 61 research publications, technical bulletins, and extension publications, including 15 book chapters.

Paulitz has served in leadership roles in The American Phytopathological Society (APS), the Canadian Phytopathological Society (CPS), USDA-ARS, and other organizations. From 1998 to 2000, he was junior and then senior councilor on the board of CPS and has been section editor of the Canadian Journal of Plant Pathology since 2000. He is presently the associate editor-in-chief of APS PRESS, and he served as a senior editor of APS PRESS (2005–2008). Paulitz also was senior editor (1994–1997) and associate editor (1991–1994) of Phytopathology. He served as a senior editor for Plant and Soil (1998–2002), was a chair of the multistate project W-147 “Managing Plant-Microbe Interactions in Soil to Promote Sustainable Agriculture”(2006), and organized the 2008 and 2009 Western Soil Fungus Conferences.

Paulitz has been instrumental in training a generation of students in plant pathology. At McGill University, he supervised 18 M.Sc. and four Ph.D. students and five post-doctoral researchers. He taught seven undergraduate, graduate, and diploma courses in plant pathology, mycology, and crop pest identification. As adjunct professor at Washington State University, he has supervised or cosupervised five Ph.D. and four M.S. students. Paulitz is deeply committed to mentoring future scientists. As part of the USDA-ARS’s outreach program, he regularly teaches science modules in schools on the Colville Indian Reservation, 170 miles from Pullman. For his tremendous commitment to math and science education for groups of Americans underrepresented in science, technology, engineering, and mathematics (STEM) professions, he was awarded both the Pacific West and the National Outreach, Diversity, and Equal Opportunity Awards for the USDA-ARS in 2008.

Paulitz’s outstanding research record, his tireless service to APS, and his commitment to the education of current and future scientists qualifies him for selection as fellow of The American Phytopathological Society.

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Patrick M. Phipps received his B.S. degree in biology from Fairmont State College, WV, in 1970, his M.S. degree in plant pathology in 1972 from Virginia Tech, and his Ph.D. degree in plant pathology in 1974 from West Virginia University. His major professor was the distinguished mycologist H. L. Barnett. He spent nearly 4 years at North Carolina State University as a post-doctoral and visiting assistant professor in plant pathology, and he had responsibilities for research on the biology and control of Cylindrocladium black rot of peanut and for teaching in the General Plant Pathology course. In 1978, he was appointed assistant professor in the Department of Plant Pathology, Physiology, and Weed Science (PPWS) at Virginia Tech and was stationed at the Tidewater Agricultural Research and Education Center at Suffolk. His assignment was to conduct research and extension projects on peanut diseases, mainly those associated with fungi and nematodes. Later, he included other crops grown by peanut farmers in southeast Virginia, namely corn, soybean, cotton, and small grains.

Phipps has an outstanding record of sustained, high-quality research and of bringing results of his research to grower clientele through extension and outreach efforts. In his research projects, Phipps has sought to implement effective, economical, and safe control measures for important field crop diseases. He has had phenomenal success in finding and validating scientifically sound approaches to maximize profits and to minimize pesticide usage, thus lessening the risk to farm workers, the environment, and the general public. To enhance his own expertise, he has cooperated extensively with colleagues at Suffolk, the Virginia Tech campus, and locations throughout the South. Among his cooperators are plant pathologists, agronomists, engineers, and meteorologists, as well as several graduate students and a dependable staff, all of whom are recognized in publications. Results of his research greatly enhance his extension program to the degree that in his commodity-oriented programs, extension, and research can hardly be separated.

The following activities highlight some of his significant contributions.
The Virginia Peanut Leaf Spot Advisory was developed in 1981 in cooperation with USDA scientists and was improved through inputs from his graduate students. The advisories were issued as a recorded message daily on a toll-free Peanut Hotline. This program reduced the former seven applications of fungicides on a 14-day schedule to only three or four timely applications per season. On Virginia’s peanut acreage, this program saved farmers about $3 million annually (1981–1990) and reduced fungicide usage by 125 tons annually (1985–1990). Savings have continued to the present, although the peanut acreage has been reduced because of the declining value of peanuts over the last decade.

In 1991, Phipps implemented a Peanut/Cotton Weather Network (PCWN), which provided electronic weather-based advisories for county agents and growers to make timely disease management decisions. The program output was delivered as recorded toll-free advisories on the Peanut Hotline. The Peanut/Cotton InfoNet was established in 1995 as an additional, Internet-based way to get information out to clientele. This work was the subject of an invited feature article in Plant Disease (81:236-244) in 1997.

Control of Sclerotinia blight has been a challenging problem for plant pathologists. Through persistent screening and field testing, Phipps found fluazinam to give excellent control of Sclerotinia blight in addition to Rhizoctonia pod and stem rot and to southern blight caused by Sclerotium rolfsii. Control of these diseases with fluazinam represented a great stride toward improving the efficiency of disease control. Timely application was keyed by daily advisories through the PCWN and Peanut Hotline. Cultivar choice, timely planting and harvesting, seeding rate, and crop rotation each contributed an increment of control as well. For this work, he received the William F. Murphy Technology Award from Virginia Tech in 2001 in recognition of his leadership in the use of electronic technologies in cooperative extension.

Collaborative research with Elizabeth Grabau has recently produced new peanut germplasm that is highly resistant to Sclerotinia blight. Their approach was to isolate an oxalate oxidase gene from barley, insert it by recombinant DNA techniques into plants of three commercial cultivars, and test the transgenic progenies for ability to resist the disease. Four years of field testing have shown effective disease control and increased yields. Tests are in progress for satisfying regulations for release of transgenic cultivars to growers. The product of this research was the first demonstration and use of transgenic germplasm for control of a peanut disease.

Phipps was the first to develop and implement an effective strategy for control of Cylindrocladium black rot (CBR) of peanut using metam sodium. Today, CBR is managed by an integrated pest management program involving sanitation, variety selection, crop rotation, planting date, soil fumigation, and scouting, all developed or refined by Phipps, colleagues, and students.

Diagnostic and Predictive Nematode Assays, in cooperation with Jon Eisenback and the Nematode Laboratory at Virginia Tech, have enabled growers to accurately manage use of nematicides in field crops. In 1989, growers reduced granular nematicide usage by 212 tons over previous years, saving $800,000 and lessening environmental impact.

Phipps has served on several committees of APS and on the editorial boards of Plant Disease, Biological and Cultural Tests, Fungicide and Nematicide Tests, and Plant Disease Management Reports, and he currently serves as a senior editor of Plant Health Progress.
His actions, successes, and excellence as a plant pathologist have been recognized and honored consistently by statewide organizations, commodity groups, colleagues, and professional organizations.

Awards include citations from the Virginia Peanut Growers Association (1979), the Virginia Cooperative Extension (1994, 2001), the Virginia Crop Consultants Association (2000), the American Peanut Council (2000), the Southeast Farm Press (2005), the Virginia Tech Agricultural Alumni Organization (2007), the Virginia Soybean Association (2007), and the Virginia Agribusiness Council (2008). He is a six-time winner of the Bailey Award from the American Peanut Research and Education Society (APRES) for best paper presentations (1985, 1990, 1999, 2000, 2002, and 2007). In 1994, he was the recipient the APS Excellence in Extension Award.
 

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Herman B. Scholthof was born in Kring van Dorth, Gorssel, the Netherlands, in 1959. He was raised on a farm and, after completing an agricultural college degree in plant research, he attended Wageningen University to obtain his B.S. degree, followed by an M.S. degree in 1986 in the Laboratory of Virology headed by Rob Goldbach. For his dissertation research at the University of Kentucky, he investigated gene expression of caulimoviruses with Bob Shepherd. After finishing his Ph.D. degree in 1990, he relocated to the University of California-Berkeley for post-doctoral studies on Tomato bushy stunt virus (TBSV) with Andy Jackson. In December 1994, Scholthof joined the faculty of the Department of Plant Pathology and Microbiology at Texas A&M University and was promoted to associate professor with tenure in 2000 and to professor in 2005. During sabbatical leaves, he worked as a visiting professor at Harvard Medical School in 2002 and 2003 and at The Boyce Thompson Institute-Cornell University in 2009.

Scholthof had very successful doctoral and post-doctoral experiences. Findings he reported as a graduate student remain highly cited because they involved the discovery of a new regulatory mechanism in eukaryotes that permits translation of polycistronic mRNAs. At the University of California-Berkeley, he continued to make important contributions using TBSV as a model system to study plant virus movement. For instance, Scholthof showed that the capsid protein is not necessary for TBSV to systemically invade some plant hosts. While at Texas A&M University he used this property to develop a TBSV-based gene-vector system that has since been used for groundbreaking research worldwide. Current industry-supported efforts aim to refine and expand the utility of TBSV components in biotechnology.

Much of Scholthof’s work focuses on how TBSV interacts with its hosts to establish systemic invasion and induce symptoms. Foremost, he discovered that two TBSV proteins (P19 and P22) expressed from the same mRNA in plants have entirely different host-dependent roles in pathogenesis. Scholthof elegantly demonstrated the nature of the P19 protein as a pathogenicity factor and found that biological properties of P19 relate to its role as a suppressor of RNA silencing to protect TBSV RNA from degradation, by sequestering short-interfering RNAs (siRNAs) during infection. Structural studies by others provided an explanation for Scholthof’s observations regarding the effect of specific mutations on the structural integrity, biological activity, and siRNA capturing ability of P19. Very recently, he revealed some novel host-dependent properties associated with P19 that appear unrelated to siRNA binding. Another set of original observations made by Scholthof is that the function of P19 is controlled by context-dependent “leaky scanning” to yield a dosage of P19 sufficient to sequester high levels of siRNAs, which is necessary for its efficacy as a suppressor of RNA silencing. Because P19 binds siRNAs in a sequence nonspecific manner, it has become a preferred tool of researchers in the elucidation of RNAi pathways in plants, yeast, and Caenorhabditis elegans.

In this context, Scholthof is widely recognized as an effective and enthusiastic collaborator. He is most generous in distributing TBSV and P19 research materials, which has allowed several dozen plant virology, C. elegans, medical, and molecular biology laboratories to perform experiments that would otherwise not have been feasible. Recently, Scholthof’s group exploited P19-defective mutants to successfully activate a prolific antiviral RNA-induced silencing complex (RISC) in plants. The antiviral RISC was isolated and shown to be programmed with TBSV siRNAs, and it specifically cleaved TBSV RNA in vitro in a divalent cation-dependent manner. This was the first such evidence for an antiviral RISC for any organism and represented a major biochemical advance for the discipline of RNA silencing.

An important distinction of Scholthof’s program is that, while many plant virologists strictly use Nicotiana benthamiana or Arabidopsis thaliana as experimental systems, over the years Scholthof has repeatedly demonstrated that findings with these plants cannot necessarily be directly extrapolated to other (crop) species. Scholthof’s philosophy, as he promulgated in a review article in Plant Physiology, is that critical meaningful information must be obtained outside the perimeter of “model” plant systems, not only in studying virus-host interactions but plant-microbe interactions in general.
Scholthof has also developed the molecular tools to investigate a newly emerged virus transmitted by the wheat curl mite. He reported the first biomolecular characterization of Wheat mosaic virus, a pathogen with no obvious similarities to known viruses, that might serve as an example to elucidate the etiology of similar mite-transmitted diseases.

Scholthof is an enthusiastic teacher of graduate courses in plant virology, molecular methods in plant-microbe interactions, theory of research, and virus gene vectors. He is much sought after as a graduate and undergraduate student mentor and serves on numerous student dissertation committees. He also is a founding member of the Texas A&M Intercollegiate Faculty of Virology. Scholthof has a very well-funded research program and an outstanding record of publication in top-ranked peer-reviewed journals, including Proceedings of the National Academy of Sciences, Journal of Virology, Virology, and Molecular-Plant Microbe Interactions.
In 2004, Scholthof was selected to present a prestigious American Society for Virology State-of-the Art Lecture, and in 2007, he received the APS Ruth Allen Award. Scholthof has served as a panel member for National Institutes of Health, National Science Foundation, and USDA. He was an associate editor and senior editor for both Molecular-Plant Microbe Interactions and Phytopathology and is on the editorial boards of Virology and the Journal of Virology. He regularly organizes, cochairs, and speaks at APS symposia and brings his students to present their research at APS meetings. While Scholthof has an exemplary record of service for APS, his most significant and lasting contributions are his original research findings. He has developed an outstanding, innovative program on the host-dependent roles of virus-encoded proteins, RNA silencing-related host defense mechanisms, and newly emerging diseases.
 

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Robert S. Zeigler is currently the director general of the International Rice Research Institute (IRRI) in the Philippines. This position caps an exemplary career of more than 20 years in international agriculture, with a focus on improving crops for developing countries. His service started after receiving his undergraduate degree in biological sciences from the University of Illinois, when he joined the Peace Corps as a secondary school science teacher in Mokala, Zaire. He returned to the United States to complete his M.S. degree in botany, with a specialization in forest ecology, from Oregon State University and his Ph.D. degree in plant pathology from Cornell University. He turned his skills and energies again to international agriculture, where he has held positions at the Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia; the Institut des Sciences Agronomique du Burundi (ISABU); and the International Rice Research Institute (IRRI, Philippines).

From early in his career, Zeigler viewed that all possible tools must be at least tested for application to crop improvement. Beginning with leading the effort to routinely use rice anther culture as a breeding tool in the 1980s in South America, he steadily adopted and developed new molecular techniques and approaches to solve resistance breeding and disease management problems to some of the most recalcitrant plant pathogens of rice. Zeigler was an active participant in the Rockefeller Foundation Rice Biotechnology Network from its inception. He has led innovative research on applying molecular markers in both crops and pathogens to predict effective resistance gene combinations and aid breeders in combining these in finished varieties. In recognition of his many accomplishments and contributions, APS bestowed upon him our prestigious International Service Award.

Over his career, Zeigler’s research has targeted problems involving viral, bacterial, and fungal plant pathogens. His research has involved many important crop species, including potato, cassava, corn, rice, wheat, and sorghum. In addition to crop- and disease-specific research, he also participated in and led cropping system and natural resource management research in Africa, Asia, and Latin America. Thus, he has an exceptionally broad understanding of the range of issues confronting crop improvement globally and is keenly aware of the biophysical and socioeconomic circumstances that set crops and cropping systems apart.

In addition to his impressive research credentials, he held senior research management responsibilities in two international agricultural research centers (CIAT in Colombia, and IRRI in the Philippines) and was department head in plant pathology at Kansas State University. In these positions, he had direct responsibility for complex multidisciplinary research programs that included plant breeders, pathologists, entomologists, agronomists, plant physiologists, crop modelers, geographers, biometricians, rural sociologists, anthropologists, and economists. Zeigler conceived and led a number of important initiatives to bring U.S. and international scientists together in collaborative research programs. These efforts were in part successful because of his in depth understanding of the Consultative Group on International Agricultural Research (CGIAR). He conceived and led the development of the Global Cereals Comparative Genomics initiative that linked the strong U.S. basic cereals genomics and bioinformatics research community with cereals improvement programs in the CGIAR and national agricultural research programs in developing countries. The Cereal Comparative Genomics initiative planted the seed for the Generation Challenge Program (for which Zeigler became the first director).

While at Kansas State University, Zeigler was a key figure in the development of the National Plant Diagnostic Network, which links our nation’s public agricultural institutions into a distributed system that provide a means for rapid identification and response to introduced pests and pathogens critical to national agricultural security. This effort considerably revitalized the extension network within the United States. During his time as director of the Generation Challenge Program, Zeigler made his mark with a wide range of donor communities, including a large block of supporters under the European Union. In his first year with the Generation Challenge Program, he raised more than 10 million dollars to support research activities across a range of new research partnerships. Two important aspects of visionary leaders are that they can effectively implement their vision and that they recognize, adopt, and integrate the vision of others. Zeigler has exhibited both aspects, and he is very careful to credit others for their contributions to the vision.

Zeigler also chaired or was a member of a number of regional international research oversight and management committees in Latin America and Asia, including the Asian Rice Biotechnology Network. Years of working with committees whose members came from diverse cultures in Latin America, Africa, and South, Southeast, and East Asia helped him develop skills in forging consensus among scientists, administrators, farmers groups, and nongovernmental organizations from very different backgrounds and with very different expectations. He is an excellent, trilingual communicator who has interacted often with the press and electronic media and is frequently invited to speak on many issues, for example, agricultural biotechnology and biosecurity. He has been an invited speaker at many APS and other international symposia and colloquia over the years.

Zeigler became the director general of the IRRI in 2005. Under his leadership, IRRI has embarked upon a new strategic plan to address poverty, human health, and environmental issues via a vigorous rice research agenda. His quality as a leader and strong advocacy for quality science mark his first 2 years at IRRI.

Zeigler has a rare breadth and depth of research and agricultural development experience that nicely complement and provide credibility to his leadership skills. His communication skills are superb—making him a perfect “ambassador” for international agriculture, in general, and plant pathology specifically. These combined attributes of quality research and leadership that Zeigler has directed at international agriculture have earned the formal and high-profile recognition by our society embodied in the APS Fellow Award. This award will suitably recognize his outstanding scientific achievements as well as his superb contributions to leadership important to the society and our profession.

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EXCELLENCE IN EXTENSION AWARD:

This award recognizes an APS member for excellence in extension plant pathology.

Anne E. Dorrance was raised in New York State. She received her A.S. degree in biology from Herkimer County Community College, her B.S. degree in forest biology from SUNY College of Environmental Science and Forestry, her M.S. degree in plant pathology from the University of Massachusetts, Amherst, and her Ph.D. degree in plant pathology from Virginia Polytechnic Institute and State University. She completed a post-doc at Washington State University Research Unit in Mt. Vernon, working with Debra Inglis examining diversity and host resistance to the new strains of Phytophthora infestans. In the fall of 1997, she joined the Department of Plant Pathology at The Ohio State University (OSU) as an assistant professor with responsibilities in soybean research and field crop extension. She is located at the Ohio Agricultural Research and Development Center in Wooster. She was promoted to associate professor in 2003. Her current appointment is 40% extension and 60% research.

Dorrance has developed a national outreach program on the management of key soybean diseases, including Phytophthora root and stem rot and soybean rust. She was chair of the NCDC202 Committee for Soybean Rust when heavy losses were being reported in Brazil. One late Friday afternoon, upon answering the phone from OSU Extension Director Keith Smith, Dorrance was tasked with writing a white paper by Monday a.m. for extension needs for Asian soybean rust. This led to a successfully funded grant from Smith Lever Funds for the development of training tools, including preserved rust infected leaves (from South Africa), an ID card, and soybean rust fungicide manual.

Dorrance is currently an associate editor for Plant Disease and coordinator for the 2009 APS Soybean Rust Symposium. She has also served APS as secretary-treasurer of the North Central Division (2002–2005), chair of the Host Resistance Committee (2001–2002), and member of the Cultural Diversity Committee (1999–2000) and the Graduate Student Committee (1995–1996).

Dorrance has led the teams that have assembled key information for producers, certified crop advisors (CCAs), and county educators. She has developed extension programming, which incorporates “hands-on” demonstrations for identification and management of key soybean diseases in the north central region. In addition to Phytophthora root and stem rot and soybean rust, she has provided outreach on many diseases, including Sclerotinia stem rot, soybean cyst nematode, brown stem rot, and seedling pathogens Pythium spp. and Rhizoctonia solani.

Dorrance is a consummate extension specialist who is always on the lookout for “teachable moments”. She states that her most rewarding work is with producers, educators, and CCAs when she can really teach them about plant pathology, whether it is identifying a pathogen or the concept of resistance. The “hands-on” workshops have been very instrumental in helping clientele really understand some of the more challenging concepts. At one of these workshops, Dorrance brought in some root samples with soybean cyst nematode, with white females clearly visible. One of the attendees could not believe that he could see them. He said his wife told him that they were big enough to see, but he hadn’t really believed it. Dorrance, satisfied that he had now learned how to spot soybean cyst nematode, responded that he might learn to listen to his wife more!

Nationally, Dorrance is recognized as an expert in soybean diseases and she has been a steady and productive leader in the national soybean rust strategic plan. She has been a clear voice and champion of the producers, and her opinions, ideas, and hard work have earned her respect by colleagues across the country. Dorrance has received several awards and honors for her outreach and service, including the American Soybean Association Special Meritorious Award. In addition, she was part to of the Asian Rust Team that was honored by the USDA with the Secretary’s Honor Award for Excellence. She has also received honors such as the Ohio Extension Agents Association Personnel Service Award, the Ohio Chapter of Epsilon Sigma Phi Team Award, and an Outstanding Achievement Award from the Ohio Soybean Council.

Dorrance has written 214 extension newsletter articles and 34 peer-reviewed publications. Also, she has made 190 extension outreach presentations (in-state and out-of-state) and 28 research presentations.

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EXCELLENCE IN INDUSTRY AWARD:

This award recognizes outstanding contributions to plant pathology by APS members whose primary employment involves work outside the university and federal realms either for profit or nonprofit.

Charles Mellinger, director of technical services and vice president of Glades Crop Care, Inc. (GCC) was born in Lancaster, PA. He earned his B.A. degree at Goshen College, followed by a Ph.D. degree and post-doctoral study at Michigan State University. From 1970 to 1978, Mellinger was an employee of Yoder Brothers, Inc. in Ohio and Florida, where he was responsible for developing programs for detection, diagnosis, and control of diseases affecting carnations, chrysanthemums, and foliage crops. Based on his leadership, cost-savings programs, and effective disease control practices, Mellinger served as corporate manager of plant health, directing the research in laboratory, greenhouse, and field programs.

In the 1970s, Carnation etched ring virus (CERV) was causing major economic losses for the U.S. carnation industry. Mellinger introduced the first large-scale indexing program for the detection of CERV. The program was based on the use of Saponaria as the indexing plant, a novel approach to thermotherapy, and the use of only apical dome tissue culture for propagation. This was a major contribution to Yoder Brothers, the largest foundation stock propagator in the United States.
Mellinger’s commercial-scale indexing program for detection and elimination of CERV restored grower confidence in the Yoder product and increased national and foreign sales by 30% while significantly reduced indexing costs.

Yoder Brothers was the earliest commercial chrysanthemum propagator with a program involving production of pathogen-free foundation stock from thousands of clones maintained in sanitary greenhouses. Mellinger developed an aseptic system of clone maintenance, thus eliminating the annual need of the costly indexing and greatly improving supply reliability.

At Yoder Brothers, Mellinger determined that an important foliage disease caused by Erwinia originated in the irrigation water of the Caloosahatchee River. Knowing this, a chlorination system was installed, bringing this disease problem under total control.
In 1980, Mellinger joined GCC in Jupiter, FL, and over the next 28 years he worked with his wife and CEO, Madeline Mellinger, to develop and expand their crop consulting business. GCC conducts advanced crop scouting and pest and disease analyses to generate profitable and environmentally sound advice to farmers. They have developed, along with state universities, integrated pest management (IPM) programs for more than 45 fresh market vegetables planted to more than 65,000 acres. Mellinger and his staff provide scouting and consultation services to one-third (value ~ $150 m) of the Florida tomato industry along with other important crops, such as sweet corn, bell peppers, leafy greens, and cucurbits. He oversees two research farms that conduct, on average, 75 efficacy and residue trials annually on vegetables, citrus, and sugarcane.

Under Mellinger’s leadership, GCC was the first crop consulting firm in the country to invest systematically in measuring IPM adoption along a continuum within its grower base. With pesticide resistance management as a central theme, they implement preventive practices to reduce pesticide interventions in addition to pesticide class rotations. Their success in managing bacterial spot of tomatoes and peppers lies in carrying out a whole series of practices, including use of disease-free transplants, strict field sanitary practices, and a correct fallow management program. Loss of yield and quality are minimized when all of these recommendations are conscientiously applied. Mellinger and his coworkers have documented that growers stand to lose $2,000 per acre if they do not practice preventive IPM recommendations for bacterial spot.

Another major disease limiting tomato production in Florida has been Fusarium crown rot. By focusing on the biology of the pathogen, Mellinger recognized that, by maintaining a nonfluctuating water table and planting crown rot-free transplants, damage caused by the disease would significantly decrease. Because of his contributions to the management of this pathogen, major losses caused by this disease over the past decades are now under acceptable control.

In 1990, GCC discovered Thrips palmi in Florida, the first find of this damaging thrips species in North America. GCC had recognized that accurate identification of T. palmi versus other thrips that vector Tomato spotted wilt virus (TSWV) was essential. Using grants (SBIR) awarded to GCC and in cooperation with the University of Florida, in 1998 a software package was developed and marketed for the identification of vegetable thrips.

Two viral diseases, Tomato yellow leaf curl virus (TYLCV) and TSWV, have been the bane of tomatoes and other crops in the Florida vegetable-growing region. Mellinger and GCC advocate the adoption of a wide range of practices for management of both diseases. For TYLCV, they include strategic scheduling and placement of plantings, correct postharvest crop destruction, elimination of disease and vector reservoirs, and thorough, accurate scouting of the population levels and life cycle stages of the silverleaf whitefly (SLW) vector. They promote region-wide TYLCV management via geo-referencing the SLW population levels and virus incidence and use a GIS database for across time evaluations and interpretations. Growers following the GCC recommendations have significantly minimized losses caused by TYLCV.

Mellinger and GCC have been at the forefront of managing TSWV in vegetable crops since it was first identified in Florida in 1985. GCC promotes the use of nonchemical preventive practices, use of reflective mulch, roguing infected plants, planting resistant varieties, and conservation of the minute pirate bug, a thrips vector predator.
Carrying out biointensive IPM in Florida’s vegetable-growing areas is about as challenging as IPM gets. One of the remarkable initiatives Mellinger and GCC have made over the years was to move from an industry dominated by the use of hard pesticides to one based on the commercial implementation of biointensive IPM. As a tribute to this advancement of both the practical arts and science of IPM, GCC has been awarded the EPA’s Champion Award for “Outstanding Efforts to Reduce Risk from Use of Pesticides” for 2003, 2004, 2005, and 2006. Mellinger has shared knowledge, experience, and data widely and unselfishly. Mellinger and GCC have conducted a considerable amount of original research using the highly competitive SBIR, SARE, PMAP, and RAMP grants, totaling more than 1.5 million dollars. GCC has found solutions to key pest problems using IPM practices, the development of pesticide resistance management strategies and pioneered methodologies to measure IPM adoption and impact.
 

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EXCELLENCE IN TEACHING AWARD:

This award recognizes an APS member for excellence in teaching plant pathology.

H. David Shew is a professor in the Department of Plant Pathology at North Carolina State University (NCSU) and a native of Leland, NC. He received his B.S. degree in biology from Greensboro College in 1974 and his master’s (1977) and Ph.D. (1980) degrees in plant pathology from NCSU. Shew has demonstrated excellence in teaching in a diversity of plant pathology undergraduate and graduate courses for more than 25 years.

For 11 years, Shew has taught a highly successful introductory undergraduate course—Principles of Plant Pathology. Shew brings much interest and enthusiasm to the teaching of plant pathology by introducing students to the most up-to-date concepts and principles in the field that reflect the latest research findings. When one attends his lectures and laboratories, one quickly realizes that Shew does a great job of getting and keeping the students’ attention in class. He has an inherent and unique ability for explaining complex concepts and principles in a format that is easy to understand and follow. He works with each class to show students that he wants to be a part of their educational, personal, and professional development. The methodologies used to accomplish these goals vary with the unique personality of each class, but they are all rooted in his fundamental desire to empower students to believe in themselves, inspire them to find their passion for new knowledge and its application, and encourage them to set goals and strive to achieve those goals. His students are encouraged to interact during lectures as questions arise. Students in the course are predominately from the crop science and horticultural science curricula. Shew is able to provide relevant examples for these students due to his extensive experience with field and horticultural crop production practices and extensive knowledge of diseases associated with these crops.

In addition to his strong lecture skills, Shew is an innovator and leader in the adoption and development of new and novel instructional technology. For instance, he recognized the need to bring technical terms unique to plant pathology to students in a new system of delivery. With assistance from the Distance Education and Learning Technology Applications (DELTA) program at NCSU, Shew converted his course glossary into an integrated electronic “flashcard learning tool” that provides instant feedback for the students. He also integrated an audio pronunciation system for the terms. Images illustrating the term are available within the same window, enabling students to view a picture to associate with the term being pronounced. An additional online innovation is an animated movie that presents the steps in understanding the gene-for-gene concept. In a series of screens that includes Shew narrating, students are led step by step through the concept with animation that illustrates each step at the molecular and structural level. This is a very powerful learning tool, as students can watch the video at their own pace and return to selected segments as needed. DELTA has received numerous requests from instructors in other courses across the campus to develop software and technologies similar to that developed by Shew.

In the laboratory, Shew uses a hands-on approach to teaching concepts and principles of plant pathology. He provides demonstrations and experiments weekly that convey in a clear and concise manner the concepts and principles under study. The laboratory also offers students an opportunity to explore questions from lectures in greater detail. One component of the laboratory is the DeBary Quiz Bowl at the end of the semester, in which teams of students compete to answer plant pathology-related questions. The enthusiastic encouragement from the audience of students leads to greater interaction and serves as a nice capstone to revisit information covered in the course as students begin to review for their final exam. A virtual plant disease diagnosis program also allows the students to follow a procedure used in our Plant Disease and Insect Clinic. Students enter the virtual clinic and interact with various stations that allow them to formulate an hypothesis and make real-world decisions in a logical and sequential process toward diagnosis of a plant disease.
Shew has taken his enthusiasm for teaching in the classroom and developed a distance education version of his Principles of Plant Pathology course that utilizes many of these same teaching technologies. Students may use a set of DVDs or stream course content for lecture and lab material. Each presentation includes a video of a presentation plus the PowerPoint slide with course content. In addition, a number of class exercises and other learning modules are included as part of the online course website.

Shew’s ability as a teacher and classroom innovator has been well recognized. He is clearly a leader at NCSU in the development of web-based instruction utilizing modern technologies. He has been an invited participant in numerous workshops at NCSU, at statewide conferences and national meetings, and in departments of plant pathology. Shew’s philosophy of education is best presented in his own words: “I will never lose sight of the fact that the most important ingredient in my success as a teacher is hard work and the carefully cultivated relationships and trust that I work hard to build with students in each of my classes. There will never be a substitute for building these relationships, and it will always serve as the foundation of my teaching philosophy, even as I cope with the challenges brought on by teaching a distance education class and reaching new audiences in our new virtual realities.”

Shew’s recognition in teaching is reflected in multiple teaching awards, including election to the Academy of Outstanding Teachers in 2002, second place in the Gertrude Cox Award for Innovative Excellence in Teaching and Learning Technology in 2006, and the Alumni Distinguish Undergraduate Professor Award in 2008. The latter award represents the most prestigious award granted to faculty teaching undergraduate courses at NCSU.
 

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INTERNATIONAL SERVICE AWARD:

This award recognizes outstanding contributions to plant pathology by APS members for countries other than their own.

Richard A. Sikora is professor and head of Soil Ecosystem Phytopathology & Nematology, Institut für Pflanzenkrankheiten, Bonn, Germany. Sikora was born December 30, 1943, in Norfolk, VA. He graduated from Eastern Illinois University in 1966 with a B.S. degree and also received an M.S. degree from this same institution in 1967. He received his Ph.D. degree in 1970 from the University of Illinois. In 1971, he began his international experience as a USAID-supported visiting assistant professor at G.B. Pant Agricultural University in India. From 1971 through 1974, he was post-doctoral fellow at the University of Bonn, supported by the German Science Foundation. Since that time, he has been a faculty member at the Institut für Pflanzenkrankheiten, University of Bonn, where he has maintained an active research and teaching program in nematology, soil microbiology, and biological control. He has also maintained an active international program in these areas throughout his career through student research and consultation in the tropics and subtropics. Nineteen of 57 master’s theses and 36 of 72 Ph.D. theses completed under his direction were done by international students from 23 different countries. The majority of the research was done in these students’ home countries, where many have become national leaders. In addition, he has had 21 post-doctoral research fellows in his lab, many of which have cooperated in his research projects with 19 countries and CGIAR centers, including IITA, ICIPE, ICARDA, CIMMYT, AVRDC, ICRISAT, CATI, and INIBAP. He and his students have conducted research in Thailand, the Philippines, Taiwan, Australia, India, Syria, Egypt, Israel, Tunisia, Tanzania, Uganda, Kenya, United States, Cameroon, Costa Rica, Tonga, Guatemala, and Brazil. These students and post-docs have coauthored 118 refereed journal articles and 111 technical publications. In addition, he has authored or coauthored nine books or proceedings, 28 book chapters, and two handbooks for plant pathology practical courses, and he has presented 28 invited papers at international meetings. Much of this work has been funded by grants from the German Ministry for Science and Technical Cooperation, the German Foreign Ministry, the German Development Foundation, FAO, USAID, and the World Bank.

Since 1971, he has had both short- and long-term overseas research consultancies to study the distribution, importance, and control of plant-parasitic nematodes, soil insects, and soilborne diseases and to recommend quarantine and IPM programs for countries, including India, Tunisia, the Philippines, Kenya, Tanzania, Uganda, Egypt, Samoa, Yemen, Syria, Bahrain, Lebanon, Cyprus, Niger, Thailand, Tonga, Yugoslavia, Guadeloupe, Benin, Malawi, Madagascar, Brazil, Morocco, Myanmar, Costa Rica, and Taiwan.

Sikora has provided valuable leadership in international agriculture, including chair of the CGIAR System-wide IPM Initiative, vice chair of the ATSAF Council for Tropical and Subtropical Agricultural Research, coordinator of the Federal Council for Tropical and Subtropical Agricultural Research (ATSAF) Scientific Commission for innovative approaches to pest and disease management, liaison scientist of the German Ministry of Technical Cooperation to ICARDA and the International Center for Insect Physiology and Ecology, director of the board of the University of Bonn Master Degree Program-Agricultural Science and Resource Management in the Tropics and Subtropics, and founder and course director of the Inter-University Consortium for Rotational Advanced Studies Program for Graduate Students in International Phytopathology and Plant Protection, as well as convener for International Organization for Biological Control Working Groups on soil pests and multitrophic interactions and integrated control in the soil. His current international research projects are focused on reduction of pesticides for control of banana and plantain pests and diseases in Africa and Central America, use of atoxigenic Aspergillus flavus strains on maize to reduce aflatoxicosis in Nigeria and Benin, use of biological control of soilborne pathogens and root knot nematodes in vegetable seedlings using fungal and bacterial antagonists, and use of fungal and bacterial endophytes for control of lesion nematodes in both oxic and anoxic rice production. The aflatoxin project is being done with Peter Cotty, USDA-ARS. The banana research has focused on use of tissue culture plantlets where nonpathogenic endophytic Fusarium oxysporum are introduced and used to induce systemic resistance and on microbially enhanced biodegradation of nonfumigant nematicides.
Sikora is actively involved in teaching at the University of Bonn and currently teaches graduate courses in Biological System Management, Methods and Experimental Techniques—Soil Ecosystem Phytopathology, Biodiversity: Conservation and Utilization, Advanced Phytonematology, Plant Protection and the Environment, and Integrated Management of Pests and Diseases. He teaches undergraduate courses in Introductory Plant Pathology and Field Diagnosis and at International Agricultural Research Centres.
Sikora has received numerous awards, including being selected as fellow for the Society of Nematologists, the European Society of Nematologists, and the Indian Academy of Sciences. Other awards include the German Industrial Award in 1992, the University of Ghent Van den Brande Award for Science in 2002, and the University of Illinois Alumni Association Award of Merit in 2004.

He is an active member of The American Society of Phytopathology, American Society of Nematologists, German Phytopathological Society, European Society of Nematologists, Society of Tropical American Nematologists, Canadian Society of Mycology, International Society of Biological Control, and Association for International Agriculture. He has provided leadership on many committees and boards for these societies.
 

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LEE M. HUTCHINS AWARD:

This is an award to the author or authors of published research on basic or applied aspects of diseases of perennial fruit plants (tree fruits, tree nuts, small fruits, and grapes, including tropical fruits, but excluding vegetables).

 James E. Adaskaveg was born in Waterbury, CT, in 1960. He received his B.S. degree in agronomy in 1982 at the University of Connecticut, Storrs, and his M.S. and Ph.D. degrees in plant pathology in 1984 and 1986, respectively, at the University of Arizona, Tucson. He was post-doctoral researcher and subsequently research plant pathologist/lecturer in the Department of Plant Pathology at the University of California, Davis, from 1986 to 1990 and 1990 to 1995, respectively. In 1995, Adaskaveg joined the faculty of the Department of Plant Pathology, University of California, Riverside, where he is currently professor of plant pathology with statewide responsibilities in tree fruit and nut pathology. Adaskaveg is recognized nationally and internationally for his outstanding contributions on the biology, epidemiology, and management of tree pathogens, including postharvest fruit decays. He received the Almond Research Appreciation Award in 1997 for his investigation of almond anthracnose, the Cherry Man of the Year Award in 2003 for his pre- and postharvest research on brown rot of sweet cherry, and the Albert G. Salter Memorial Award in 2006 for his research on Septoria spot and postharvest decays of citrus. For the last 3 years, he has been the scientific advisor for USDA-APHIS in negotiations with the Korean government on the exportation of California oranges to Korea.

Adaskaveg was associate editor of Phytopathology from 2005 to 2007, and he is serving on the APS Mycology, Pathogen Resistance, and Postharvest Pathology Committees. He has served the Pacific Division of APS as president (2002–2003) and was on committees within the division for 18 years. He also has organized two well-attended field trips on tree fruit diseases during the 2005 and 2007 APS Annual Meetings.

Adaskaveg is recognized specifically for his contributions to our understanding of anthracnose diseases. In the early 1990s, when the California almond industry suffered devastating losses from an unknown disease, he was fundamentally involved in identifying and characterizing the causal pathogen, Colletotrichum acutatum, studying the epidemiology of the disease, designing effective management strategies, and investigating the infection process of the pathogen. He reported this work in six publications in Phytopathology and Plant Disease, in several abstracts at APS and other meetings, and in a book chapter (published by APS PRESS).

Adaskaveg and his research team demonstrated that two distinct subpopulations of C. acutatum were involved in anthracnose outbreaks that differ in colony morphology and spore characteristics, molecular fingerprints, and temperature-growth responses. These studies helped to correctly identify the cause of almond anthracnose as C. acutatum and not C. gloeosporioides in California and other almond-growing regions. In laboratory, growth chamber, and field studies, Adaskaveg and his associates found that the pathogen not only overwinters in mummified fruit that remain on the tree, but also in fruit spurs. Furthermore, leaf symptoms and terminal dieback of twigs were found to be caused primarily by the production of phytotoxic, water-soluble compounds. Temperature and wetness duration requirements for almond anthracnose development were studied on leaves and flowers, which served as the basis for a disease model to improve timing of fungicide applications.

Subsequently, Adaskaveg and his colleagues focused their research on the infection process of C. acutatum in almond tissues, resulting in three publications in Phytopathology. Using novel methods in digital image analysis of light micrographs together with scanning electron microscopy and histological sectioning of tissues, they provided direct evidence that the internal light spots of fungal appressoria correspond to the penetration pore and the infection peg. Digital image analysis was used to evaluate infection and colonization strategies in this host-pathogen system. A unique combination of two infection strategies was found within almond petals and leaves. Based on the presence of subcuticular infection vesicles, subcuticular, intra- and intercellular hyphae of different types, and an extended biotrophic phase, almond tissue colonization by C. acutatum was described as subcuticular-intracellular hemibiotrophy and intercellular necrotrophy. During the first 24–48 h after penetration, fungal colonization was biotrophic and host cells adjacent to fungal hyphae were healthy, but later, the host-pathogen interaction became necrotrophic with collapsed host cells. The relative importance of the different stages of subcuticular-intracellular hemibiotrophy and intercellular necrotrophy during colonization of the almond host depended on the tissue infected. Thus, on leaves, subcuticular growth usually extended farther than on petals before penetration of epidermal cells. In a feature article in Plant Disease coauthored by Adaskaveg, infection strategies and life styles of different C. acutatum-host systems on fruit crops were compared that demonstrated the wide spectrum of host-pathogen interactions. Depending on the host and tissue infected, C. acutatum can exist as a necrotroph, biotroph, endophyte, or epiphyte. Thus, the pathogen develops a highly specialized relationship at the cellular level that is reflected in the disease cycle for each host-pathogen system.

Recently, Adaskaveg pioneered the visualization of pH modulation in C. acutatum-almond host-pathogen interactions. Others have described the pH modulation of host tissue based on biochemical, physiological, and molecular studies. Adaskaveg and coworkers were among the first to use pH-sensitive probes and fluorescence confocal microscopy to study host-pathogen interactions, which allowed visualization of the spatial distribution of localized pathogen-induced alkalinization in proximity to fungal infection structures at the cellular level. Ratiometric measurement of fluorescence at two wavelengths and in situ calibration allowed the quantification of pH ranges. A sequence of events in the C. acutatum-almond interaction was established that includes penetration, production of ammonia by C. acutatum, and subsequent pH modulation within almond leaf epidermal tissue to an alkaline environment that leads to colonization of the host.

Adaskaveg’s accomplishments on anthracnose diseases represent significant contributions to plant pathology. Additionally, he is an outstanding scientist in other areas of the discipline. His broad-spectrum tree fruit and nut pathology program encompasses research on fungal and bacterial diseases of many tree crops grown in California. His program elegantly merges basic and applied aspects of plant pathology. He is a frequent speaker at a range of meetings, where he enthusiastically communicates his knowledge to help solve disease problems in production agriculture.