Amy O. Charkowski was born in Madison, WI. She holds a B.S. degree in biochemistry and plant pathology from the University of Wisconsin-Madison (UWM) (1993) and a Ph.D. degree in plant pathology from Cornell University (1998). She currently serves as an associate professor of plant pathology at UWM.
Charkowski deserves the 2011 APS Syngenta Award because of her unusual breadth and depth of accomplishments at this relatively early stage of her career in plant pathology. She has combined important discoveries about the molecular basis of soft-rot diseases with development of directly applicable tools to detect, manage, and prevent crop losses. She is a truly translational researcher, in that her mind seems to naturally connect her fundamental research discoveries to disease prevention strategies. In addition to leading a highly productive research program, Charkowski also directs Wisconsin Seed Potato Certification. This $900,000/year program includes management of a tissue culture laboratory and an early generation seed farm that produces two million pounds of seed potatoes annually and an inspection program that certifies seed produced by 27 farms.
Below are descriptions of three of the several areas in which her work has had major impacts. (Numbers in parentheses refer to associated peer-reviewed publications.)
1. Pectobacterium ecology, taxonomy, and plant-microbe interactions
Pectobacterium species (formerly Erwinia carotovora) are the most common cause of bacterial soft rot of vegetables and ornamentals in the world. Charkowski and her group have worked both alone and collaboratively to understand and control this disease. They identified the most prevalent types of Pectobacteria attacking potatoes in Wisconsin, and in the process discovered a Pectobacterium subspecies previously unreported outside of Brazil and a Pectobacterium species previously unreported on potato (15, 24). They have sequenced the genomes of several Pectobacterium taxa (in collaboration with Nicole Perna’s lab) (31). These genome data enabled systematic experiments to determine the roles of novel bacterial virulence genes up-regulated in rotting potato tubers (26, 27, 30, 37). This innovative and technically demanding work has resulted in breeding efforts now focused on the appropriate Pectobacterium species, sensitive and specific assays for better testing of breeding material, and significant new basic biological insight into Pectobacterium interactions with host tubers, stems, and leaves.
2. New methods to generate soft rot-resistant crops
Charkowski’s group discovered that Pectobacterium appears to deliver only a single Type 3 effector, DspE, into host cells. This effector protein causes plant cell death and, hence, promotes pathogenesis of soft rot bacterial pathogens (20, 21). But DspE can also trigger a successful resistance response in plants that recognize it (38). Most recently, Charkowski identified a diploid potato species that resist the killing effect of DspE and also decay by Pectobacterium carotovorum. Single dominant soft rot resistance genes have long been known in some crops, such as sugarbeet, but they have never been cloned and their mechanism was unknown. Amy's group is using a simple leaf-death assay to identify plant genes that enable crops to resist the killing effects of DspE. Moving DspE-recognizing plant defense genes into potato or other crop plants is an exciting and creative new strategy to control a very destructive broad host-range plant pathogen.
3. The Wisconsin Seed Potato Program
As part of her appointment, Charkowski administers the Wisconsin Seed Potato Certification Program. This program is divided into two parts, a regulatory program that certifies approximately 450 lots of seed from 8,500 acres of seed and breeding farm fields and an early generation seed potato farm that provides Wisconsin growers with healthy seed potatoes. Wisconsin seed potato farmers grow approximately $16 million worth of seed potatoes planted by commercial growers around the United States to produce approximately $100–$150 million worth of potatoes each year (out of a national production of $3.2 billion yearly). Thus, a substantial proportion of the U.S. potatoes can be traced back to the state farm, highlighting how critical it is to maintain the health of this program. Under Charkowski’s conscientious and innovative leadership, this program is considered among the best in the world. As a result, Charkowski has hosted many visitors and trained scientists and farmers from Africa, Europe, Asia, and South America in clean seed production. Her specific accomplishments in the seed potato program include:
• Updating the state rule (akin to changing a law) that governs seed potato production to bring it into line with industry and international standards (this was a huge job!);
• Implementing a hydroponics production system for seed potatoes that has resulted in production of healthier seed potatoes and a significant decline in virus incidence;
• Improving access to seed potatoes for small conventional and organic growers in Wisconsin and launching an innovative program to produce organic seed potatoes;
• Responding effectively to ongoing finds of diseases new to the United States or to Wisconsin, including potato cyst nematode, powdery scab, and multiple viruses that cause tuber necrosis diseases (32); and
• Working collaboratively with researchers around the country to improve detection methods for diverse potato pathogens (18, 22).
Amy is enriching our profession’s future as well as its present. In less than nine years as a faculty member, she has trained eight graduate students and five post-docs, as well as dozens of undergraduate and high school students and a steady stream of international scientists seeking the latest techniques and ideas in her lab. Although she has no formal teaching appointment, she regularly teaches in several graduate courses, most notably developing a new plant virology module to fill a gap in the curriculum. Further, she is a responsible scientific citizen, serving on many grant panels and holding leadership positions in APS, the international seed potato research community, and the department. Finally, she has led a politically challenging but commendably idealistic international project to develop quality potato seed production in North Africa and the Middle East.
In summary, Charkowski’s outstanding research, teaching, and service to both the applied and the basic branches of plant pathology make her a very appropriate recipient of the Syngenta Award.