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A real-time PCR technique was applied for the quantification of trichothecene-producing Fusarium species (TMTRI assay) as well as the highly toxigenic Fusarium graminearum (TMFg12 assay) present in barley grain and malt. PCR results were compared to the amounts of trichothecenes detected in the samples to find out if the PCR assays can be used for trichothecene screening instead of expensive and laborious chemical analyses. DNA was extracted from ground kernels using a commercial DNA extraction kit and analysed in a LightCyclerÒ system using specific primers and fluorogenic TaqMan probes. Both naturally and artificially contaminated grains were analysed. The TMTRI assay and the TMFg12 assay enabled the quantification of trichothecene-producing Fusarium DNA and F. graminearum DNA present in barley grain and malt samples, respectively. Both TaqMan assays were considered to be sensitive and reproducible. Linearity of the assays was 4-5 log units when pure Fusarium DNAs were tested. The amount of Fusarium DNA analysed with the TMTRI-trichothecene assay could be used for estimation of the deoxynivalenol (DON) content in barley grain. Furthermore, the TMFg12 assay for F. graminearum gave a good estimation of the DON content in north American barley and malt samples, whilst the correlation was poor among Finnish samples. DON content and the level of F. graminearum DNA were found to be naturally low in Finnish barleys.

The TR-IFMA assay for detecting anti-DGP antibodies shows high sensitivity and specificity for the diagnosis of CD in children. In a majority of our study population, anti-DGP seropositivity preceded TGA positivity, indicating that earlier detection of CD may be possible by monitoring anti-DGP antibodies frequently in genetically susceptible children.

In this paper the latest studies dealing with genetic variation and mycotoxins ofF. avenaceum and related species are reviewed and compared to the data from chromatographic image analyses. Forty-three European strains ofFusarium avenaceum and related species were classified by chromatographic image analysis on full chromatographic matrices. The results were in most cases in agreement with those from morphological and molecular analyses and supported the separation betweenF. avenaceum, F. arthrosporioides andF. tricinctum and betweenF. avenaceum groups I and II. The mycotoxin profiles of the FinnishF. avenaceum, F. arthrosporioides andF tricinctum strains were very similar to each other. Moniliformin and enniatins were the main mycotoxins produced. A fluorogenic TaqMan PCR assay (qPCR) was used for the detection ofF. avenaceum/ F. arthrosporioides DNA in Finnish barley and wheat. The qPCR results obtained from grain samples were compared to mycotoxin levels. A correlation was found betweenF. avenaceum/F. arthrosporioides DNA and moniliformin (MON) and enniatin (ENNs) levels in barley. A correlation was also found between the combinedF. avenaceum/F. arthrosporioides/F. tricinctum contamination and MON and ENNs levels in barley in 2002, but not in 2003. This was probably due to the higher MON and ENNs levels in 2002 than in 2003. It was possible to use the DNA levels ofF. avenaceum/F. arthrosporioides to distinguish between most barley samples containing high amounts of MON and ENNs from those containing low levels of the mycotoxins.

Prevalence, species composition, genetic variation and pathogenicity of clover rot (Sclerotinia trifoliorum) and Fusarium spp. in red clover in Finland Abstract The species composition of a total of 173 red clover root fungal isolates from red clover roots from two established organic fields, a field in a transitional phase to organic and from two conventional fields was investigated based on morphology and molecular methods. Fusarium avenaceum was the most common Fusarium species overall but it occurrred less frequently in older organic fields. Gliocladium spp., Trichoderma spp. and Rhizoctonia spp. isolates were more common in the established organic clover fields, which had been under organic management for more than ten years and in one conventional field, than in a field still in the transitional phase. The taxonomical status of certain Fusarium, Alternaria and Sclerotinia isolates difficult to identify by morphological traits alone could be confirmed by species-specific primers and by comparing their ITS (internal transcribed spacer region) sequences to known sequences. The fingerprinting patterns of RAPD-PCR products could be used for the identification of fungal isolates and for studying the genetic variation among the isolates. Only one of the Fusarium isolates originating from apparently healthy red clover roots was clearly pathogenic to germinated red clover seedlings. In detached leaf experiments, the cvs Jokioinen and Ilte were more susceptible to one of the Sclerotinia trifoliorum isolates than cvs Betty and Bjursele, while all of them were equally susceptible to two other S. trifoliorum isolates. In further greenhouse experiments with intact plants it was possible to slow down the development of clover rot to some extent by means of one of the biological agents tested (Bacillus subtilis 10-VIZR, commercial name Alirin B), and almost completely by chemical control. IntroductionRed clover (Trifolium pratense) is the main perennial leguminous fodder crop with symbiotic Rhizobium bacteria for nitrogen fixation in Finland. Practically Eur J Plant Pathol (