carry out grape powdery mildew research
Robert Seem{ XE "Seem, R." }Department of Plant Pathology and Plant‐Microbe Biology, Cornell University, Geneva, New York 14456 USA
INTRODUCTION
To understand research translation, it is helpful to understand
our past efforts to extend knowledge, especially agricultural
knowledge, to those who need and benefit from that
information. The traditional term to define this process is
Extension. Extension as it exists today in the United States has a
rich history of nearly 150 years. We will examine the
development of the Cooperative Extension Service in the US,
especially at the time (mid 19th century) when educational and
research institutions were evolving dramatically (1). In that era
of change, colleges began to be more egalitarian and outward
looking (extension). Extension has survived and grown over the
years, but some of the mission fervour had faded. A renewed
commitment to extension is now embodied within the latest
buzzword of the 21st century: engagement. We will examine
how extension and engagement influence research using the
example of grapevine powdery mildew. We will consider what
drives the process and how we can sustain it. Some final
reflections look towards the future and thoughts on the value of
translating research to the field.
EXTENSION’S CREATION AND TRANSITION TO ENGAGEMENT
The Genesis of Extension It was during the American Civil War
that an innovative approach was taken to permit a broadened
reach of higher education. The Morrill Act of 1862 established a
federal partnership with states to establish centres of learning
for agriculture and the mechanic arts. The act provided tracts of
federal land for states to use or sell in order to creat “land‐
grant” colleges. Shortly thereafter (1865) Cornell University was
established as New York State’s land‐grant college. Almost thirty
years later (1894) Cornell’s first professor of horticulture, Liberty
Hyde Bailey, implemented the nation’s first extension program,
“a plain, earnest, and continuous effort to meet the needs of the
people on their own farms and in the localities.”
Extension in the 21st Century Fast forward to 2009, and the
modern Extension Service remains one of the very unique
features of American agriculture. However, it has moved beyond
farmers and addresses many aspects of rural and urban life. In
an analysis of the future of the land‐grant universities, the
Kellogg Commission exhorted these institutions to become
“engaged universities” (2). By engagement they refer to
institutions that have redesigned their teaching, research, and
extension and service functions to become even more
sympathetically and productively involved with their
communities, however community may be defined.”
MEETING THE CHALLENGE
So how does this new engagement play out for a university
researcher who has no official extension responsibility? For
those of us who carry out mission‐oriented research we are
always asking two questions: What are the challenges facing the
industry? How does my research address those challenges? In
the context of plant pathology, our first goal is to carry out good
science; but our science is always focused on solving problems as
we expand our knowledge.
GRAPEVINE POWDERY MILDEW CHALLENGES WE HAVE
ADDRESSED
Over the past 30 years with the assistance of colleagues and
students we have examined, and in some cases, redefined the
role and impact of Erysiphe necator on grape, always driven by
industry needs (e.g., 3‐5):
• The importance of early‐season disease management • The role of cleistothecia in epidemics
• Environment, ascospore release, and infection • Early season disease spread within vineyards • Effect of cold nights on mildew development • Ontogenic resistance in grape berries
• Heterogeneity of berry development and susceptibility • Diffuse mildew infection on berries and wine quality • Signals that turn sporulation on and off
• Biological control of powdery mildew by Tydeid mites
CONCLUSIONS
Our research on the biology and epidemiology of grape powdery
mildew has had a major impact on grape production in New York
and has influenced research and extension programs throughout
the US and beyond. The program is not substantially different
from many other mission‐oriented research programs, but for
those who seek to translate research to the field, this is what we
have learned:
• Be grounded – understand and appreciate agriculture • Observe; look at the big picture, but mind the little stuff • Know your patients and your pathogens
• Become engaged; know your stakeholders and deal with
them as peers
• Write proposals that are clear succinct, and interesting • Collaborate, locally and professionally
• Train the next generation; get them excited about
translational research • Have fun while doing all this!
ACKNOWLEDGEMENTS
For their vital collaborations, I thank David Gadoury and the labs
of Wayne Wilcox, Greg Loeb, Thomas Henick‐Kling, Lance Cadle‐
Davidson, and Ian Dry.
REFERENCES
1. Boyer, EL (1990) Scholarship reconsidered: priorities of the
professoriate. (Carnegie Foundation for the Advancement of
Teaching: Princeton, NJ) 147pp.
2. Kellogg Commission on the Future of State and Land‐Grant Universities (1999) Returning to our roots: The engaged institution, Report 3. (National Association of State Universities and Land‐ Grant Colleges: Washington DC) 57 pp.
3. English‐Loeb, G, Norton, AP, Gadoury, D, Seem, RC, and Wilcox, WF
(2007) Biological control of grape powdery mildew using
mycophagous mites. Plant Dis. 91, 421‐429.
4. Gadoury, DM, Seem, RC, Ficke, A, and Wilcox, WF (2003) Ontogenic resistance to powdery mildew in grape berries. Phytopathology 93, 547‐555.
5. Gadoury, DM, Seem, RC, Wilcox, WF, Henick‐Kling, T, Conterno, L, Day, A, and Ficke, A (2007) Effects of diffuse colonization of grape berries by Uncinula necator on bunch rots, berry microflora, and juice and wine quality. Phytopathology 97, 1356‐1365.
Session
6A—Cereal
pathology
Stem rust race Ug99: international perspectives and implications for Australia
R.F. ParkB, H.S. BarianaB and C.R. Wellings{ XE "Wellings, C.R." }A,BThe University of Sydney, Plant Breeding Institute, PMB 11, Camden, 2570, NSW
B
seconded to The University of Sydney, Plant Breeding Institute, PMB 11, Camden, NSW 2570
INTRODUCTION
Stem rust of wheat, caused by Puccinia graminis f. sp. tritici
(Pgt), is one of the most feared plant diseases. It was particularly
problematic in early efforts to grow wheat in Australia, being
described by McAlpine (1) as “positively injurious”. Reports of
losses in Australia include £400,000 in 1903, £2 million in 1916,
£7 million in 1947, and $200 to 300 million in 1973 (2).
Concerted efforts to control the disease with genetic resistance
began with the release of cultivar Eureka in 1938, and have led
to a decline in the incidence of the disease and in the frequency
of epidemics.
The detection of stem rust race “Ug99” in Uganda in 1999 has
had significant implications for the control of stem rust.
Referring to “Ug99”, Nobel Laureate Dr Norman Borlaug, stated
“The prospect of a stem‐rust epidemic in wheat in Africa, Asia,
and the Americas is real and must be stopped before it causes
untold damage and human suffering”
(
PATHOGENIC VARIABILITY IN AUSTRALIA
Annual pathogenicity surveys of Pgt conducted at the University
of Sydney since 1919 have provided a sound basis for rust
resistance breeding efforts. These surveys have revealed 3
incursions of 4 exotic Pgt isolates, all of which had significant
impacts on wheat production, highlighting the importance of
current exotic threats such as Pgt race “Ug99”. The surveys have
also shown clear evidence of the importance of pathogen
aggressiveness, of single step mutation and of somatic
hybridisation in overall pathogen population structure (2).
STEM RUST RACE Ug99
Since its first detection in Uganda in 1999, “Ug99” has been
detected in Kenya, Ethiopia, Sudan and Yemen, and in 2007 was
detected in Iran (3). It carries virulence matching many
resistance genes in hexaploid wheat: genes rendered ineffective
are Sr5, Sr6, Sr7b, Sr8a, Sr8b, Sr9a, Sr9b, Sr9d, Sr9e, Sr9g, Sr11, Sr15, Sr17, Sr21, Sr30, Sr31, and Sr38; those that remain
effective are: Sr7a, Sr13, Sr22, Sr24, Sr25, Sr26, Sr27, Sr28, Sr29, Sr32, Sr33, Sr35, Sr36, Sr37, Sr39, Sr40 and Sr44. Of particular
concern is virulence for gene Sr31, one of the most widely
deployed stem rust resistance genes, which remained effective
until the detection of “Ug99”. Since its first detection, two
presumed mutational derivatives with virulence for Sr24 (4) and
for Sr36 (5) have been detected in Kenya (4), and a race with
identical virulence but lacking virulence for Sr31 has been
detected in South Africa (6).
“Ug99” has had a large impact on a wide range of international
wheat germplasm. In response, the Borlaug Global Rust Initiative
(BGRI) was launched in Kenya in 2005 and acknowledged the
threat of “Ug99” to stable wheat production in eastern Africa,
and also recognised the threat posed to many other parts of the
world. More recently, an international project, “Durable Rust
Resistance in Wheat” was funded by the Bill and Melinda Gates
Foundation and is managed by Cornell University. This project
has a range of activities that include pre‐breeding, rust pathogen
surveillance and cultivar deployment.
IMPLICATIONS FOR AUSTRALIA
The Australian Cereal Rust Control Program (ACRCP) provides
support to all groups engaged in cereal breeding in Australia,
and undertakes research on the pathology and genetics of rust
diseases. This strategy has led to a robust understanding of the
resistance genes deployed in Australia, and a resulting ability to
predict response of Australian germplasm to new rust races such
as “Ug99”. These predictions have been refined by field testing
germplasm in Kenya with the assistance of the Kenyan
Agricultural Research Institute from 2005–07. Because Sr31 has
not been used widely in Australia, the greatest impact of “Ug99”
on germplasm to date has been due to virulence for Sr30,
combined virulence for Sr38 with other genes, and more
recently, virulence for Sr24 and Sr36. While virulences for Sr30, Sr36 and Sr38 have been detected in Australia, virulence for Sr24
has not. The genes Sr2, Sr12, Sr13, Sr22 and Sr26, effective
against “Ug99” and derivatives, are important contributors to
the resistance present in current germplasm.
CONCLUDING COMMENTS
Although “Ug99” may never reach our shores, it must be
regarded as a serious exotic rust threat. Whilst acknowledging
this, it is equally important not to forget other exotic rust
threats, including races of endemic cereal rust pathogens, plus
the cereal rust diseases that do not occur here (stripe rust of
barley, Puccinia striiformis f. sp. hordei; leaf rust of durum
wheat, Puccinia sp. Group II Type A; crown rust of barley, P. coronata var. hordei.
ACKNOWLEDGEMENTS
The Australian Cereal Rust Control Program is supported
financially by the Grains Research and Development
Corporation, Australia.
REFERENCES
1. McAlpine D (1906) ‘The Rusts of Australia. Their Structure, Nature,
and Classification’. (Department of Agriculture, Victoria:
Melbourne).
2. Park RF (2007) Stem rust of wheat in Australia. Australian Journal of
Agricultural Research 58, 558–566.
3. Narari K, Mafi M, Yayhaoui A, Singh RP, Park RF (2009). Detection of wheat stem rust (Puccinia graminis f. sp. tritici) race TTKS (Ug99) in Iran. Plant Disease 93, 317.
4. Jin Y, Szabo LJ, Pretorius ZA, et al. (2008). Detection of virulence to resistance gene Sr24 within race TTKS of Puccinia graminis f. sp. tritici. Plant Disease 92, 923–926.
5. Jin Y, Szabo LJ, Rouse MN et al. (2009) Detection of virulence to resistance gene Sr36 within the TTKS race lineage of Puccinia
graminis f. sp. tritici. Plant Disease 93, 367–370.
6. Visser B, Herselman L, Pretorius ZA (2009) Genetic comparison of Ug99 with selected South African races of Puccinia graminis f. sp. tritici. Molecular Plant Pathology 10, 213–222.