|Van Coller, G|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/16/2013
Publication Date: 5/16/2013
Citation: Van Coller, G.J., Boutigny, A., Ward, T.J., Lamprecht, S.C., Viljoen, A. 2013. Head blight of wheat in South Africa is associated with numerous Fusarium species and chemotypes. Meeting Abstract. Interpretive Summary:
Technical Abstract: 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 nivalenol (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.