EFS12- Book of abstracts - Contact

SESSION 3: PATHOGENESIS – EPIDEMIOLOGY AND POPULATION
GENETICS
P59 - Head blight of wheat in South Africa is
associated with numerous Fusarium species and
chemotypes
G. J. van Coller 1,2 , A.-L. Boutigny 2 , L. Rose 2 , T. J. Ward 3 , S. C. Lamprecht 4 , A.
Viljoen 2
1 Directorate of Plant Science, Western Cape Department of Agriculture, Private Bag X1, Elsenburg
7607, South Africa; 2 Department of Plant Pathology, University of Stellenbosch, Private Bag X1,
Matieland 7602, South Africa; 3 Bacterial Foodborne Pathogens and Mycology Research Unit,
Agricultural Research Service, United States Department of Agriculture, Peoria, IL 61604, USA; 4 Plant
Protection Research Institute, Agricultural Research Council, Private Bag X5017, Stellenbosch 7600,
South Africa
E-mail: altus@sun.ac.za
Fusarium head blight (FHB) of wheat is caused by numerous Fusarium species,
including trichothecene-producers. In South Africa, FHB is mostly associated with
irrigated wheat rotated with maize. Twenty symptomatic wheat heads were
collected from four cultivars each in irrigated fields during 2008 and 2009 in the
Northern Cape Province (12 sites), in KwaZulu-Natal (KZN) (seven sites), the
Free State (six sites), at four sites in the Bushveld (2009), and under dryland
conditions in the Western Cape (four sites). A total of 1323 Fusarium isolates
were obtained from kernels, identified molecularly and morphologically, and
chemotyped. Fifteen Fusarium species were isolated, with the F. graminearum
species complex (FGSC) dominant at most sites. Other Fusarium spp. included F.
avenaceum, F. brachygibbosum, F. cerealis, F. chlamydosporum, F. culmorum, F.
incarnatum-equiseti species complex (FIESC), F. lunulosporum, F. oxysporum, F.
poae, F. pseudograminearum, F. solani, F. tricinctum, the Gibberella fujikuroi
species-complex and an unknown Fusarium species. Fusarium
pseudograminearum was dominant at one location in the Free State and in the
Western Cape. Isolates representing the FGSC were identified using a
microsphere-based Multilocus Genotyping Assay (MLGT). FGSC members
included F. graminearum s.s. (85.2%), F. boothii (8.3%), F. meridionale (3.6%), F.
acaciae-mearnsii (1.4%), F. cortaderiae (1.1%), and F. brasilicum (0.4%). The 15-
ADON chemotype was most common in 2008 and 2009, the 3-ADON chemotype
in the Western Cape in 2009 and at one location in the Free State (2008 and
2009), and the NIV chemotype was most common at one site in KZN in 2009.
This extensive survey reported F. lunulosporum for the first time on wheat
worldwide and identified production areas of concern in South Africa regarding
mycotoxin contamination.
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