Meeting the Challenge of Yellow Rust in Cereal Crops - ICARDA

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Wheat Rust in Europe
Mogens S. Hovmøller
Department of Integrated Pest Management, Danish Institute of Agricultural
Sciences, Flakkebjerg, Slagelse, Denmark
The three cereal rusts—yellow rust, leaf rust and stem rust—are among the
most damaging cereal diseases in Europe. Yellow rust is predominant in NW
Europe and in coastal areas, whereas leaf rust is more prevalent in Central and
Eastern Europe. This is also the area where stem rust may cause damage,
although stem rust has not been considered a major problem in the last two
decades. The prevalence of leaf and stem rusts in Central and Eastern Europe
is probably due to generally warmer summers in these areas. The eradication
campaigns of the alternate host of stem rust, Berberis vulgaris, have decreased
survival of the fungus outside the main wheat growing season, and this may
further explain why stem rust epidemics have become less frequent. However,
the reduced attention to resistance to stem rust in European plant breeding in
the last 30–40 years, and possible effects of warmer weather due to global
warming, and warmer and more humid summers, may increase the
significance of stem rust in the future.
In many areas in Europe, wheat is grown as a high-input crop, and one to
two fungicide treatments are common, in particular in the humid areas where
other damaging diseases on wheat, namely powdery mildew and Septoria
tritici, may be prevalent. However, the increasing costs of agrochemicals and
environmental concerns about pesticides may put more emphasis on breeding
for disease resistance. In fact, breeding for resistance to the cereal rusts has
been successful in the last couple of decades. At present, about half of the
wheat area in NW Europe is grown with varieties highly resistant to yellow
rust.
Breeding and extension services are supported by annual pathogen and
disease surveys in a number of countries, including UK, France, Denmark,
Germany, Czech Republic and Hungary, and inoculated disease nurseries,
where the most recent and complex pathotypes are used for assessing
vulnerability of new breeding lines and commercial varieties, are also carried
out in several countries. During the 1990s, collaborative networks to collate
data on pathotype frequency dynamics and exchange of wheat germplasm and
exposure to ‘local’ leaf and yellow rust pathotypes were developed. The
European and Mediterranean Cereal Rust Foundation established a home page
(www.crpmb.org) where news concerning cereal rust research, breeding,
surveys, networks and meetings could be accessed.