[Truncated abstract] Sheep grazing in Western Australia have been reported to partially or completely refuse to consume pods of annual Medicago spp. These were later found to be contaminated with a number of different Fusarium species. Previous rat toxigenicity studies on 16 Western Australian Fusarium isolates from legume pasture species mostly associated with the feed refusal disorder, showed that they can cause high mortality rates. Fusarium species, predominantly associated with cereal grains, are known to produce deoxynivalenol (causes vomiting and feed refusal in animals) and/or diacetoxyscirpenol (also causes reduced feed intake in animals) as part of their array of toxigenic secondary metabolites. Furthermore, in 2004, Fusarium head blight (FHB) of wheat was reported in the south coastal area of Western Australia. The overall aim of this study was to isolate and characterise the toxigenic secondary metabolites produced by 47 Fusarium isolates associated with sheep feed refusal disorder, annual legume pastures and FHB, and also to compare the secondary metabolite profiles of pasture related and head blight of wheat related Fusaria. Attempts were made to molecularly identify 69 Fusarium isolates from pasture and wheat-growing areas in Western Australia using ten speciesspecific primers, an internal transcribed spacer primer and/or the translation elongation factor 1-α primer. Professional mycologists from the International Mycological Institute (IMI), Surrey, UK, had previously identified 44 of the 69 Fusarium isolates using classical morphological methods. Only 32 of these 44 matched the species identity when using molecular methods. Two isolates remained unidentified after using the PCR methods, while two Fusarium spp. were recorded for the first time in Australia, namely F. brachygibbosum and F. venenatum, while F. tricinctum was recorded for the first time in Western Australia.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2010|