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Fusarium graminearum as the main causal agent of Fusarium head blight (FHB) and its ability to produce trichothecenes was investigated by molecular techniques. A total of 37 strains isolated from the wheat, harvested in Serbia in 2005, 2008 and 2015, and previously designated by morphological observation as F. graminearum , were used for trichothecene genotypes characterization. The strains were identified using the species-specific primer set FG16R/FG16F while genotypic characterization was done using specific TRI13 and TRI3 sequences of the trichothecene gene clusters. The PCR assays identified all strains as species of F. graminearum sensu stricto with the DON/15-ADON genotype. The quantification of the mycotoxin (DON) was performed using the biochemical assay. The high levels of DON (>20,000 µg kg -1 ) were recorded in all of the strains from 2005, four strains from 2008 and two strains from 2015. Weather data of the investigated seasons, showed that the optimal temperature, frequent rains and high relative humidity (RH) was very favourable for the development of F. graminearum , affecting the DON biosynthesis.

Morphological, biological, and phylogenetic approaches were undertaken for the identification of pathogenic species F. temperatum in the Serbian population of F. subglutinans collected in the 1999-2010 period from Zea mays (3 root, 15 stalk, and 6 seed samples), Sorghum bicolor (two seed samples), Hordeum vulgare (one seed sample) and Taraxacum officinale (one seed sample). Based on interspecies mating compatibility analyses and the maximum parsimony analysis of EF-1α sequences, only two strains, originating from S. bicolor seed (MRIZP 0418 and MRIZP 0552), were identified as F. temperatum, while the remaining 26 single-spore strains were identified as F. subglutinans Group 2. In situ detached barley leaf assay and artificially stalk and ear inoculation of two maize hybrids demonstrated that both F. temperatum and F. subglutinans strains were medium and strong pathogens under laboratory and field conditions, respectively. These are the first data on the F. temperatum as seed-borne pathogens of sorghum, as well as pathogenicity of F. temperatum strains on maize. [ABSTRACT FROM AUTHOR]

In this study, a total of 41 poultry (chicken and laying hens) feed samples collected from different farms in Serbia in the beginning of 2014 were investigated for total fungal count, presence of potential toxigenic fungi and natural occurrence of T-2 toxin. The number of total fungi was determined using the plate count method whereas T-2 toxin was detected by enzyme-linked immune sorbent assay (ELISA) method. Relative high percent of investigated poultry feed samples (43.90%) had the total fungal count 1 - 7 x 10² CFU g-1, while in 29.27% of the samples that number was 1.4 - 14 x 104 CFU g-1. In regard to potentially toxigenic fungi, species of Fusarium genus were isolated in most of poultry feed samples (58.54%), while species from genus Alternaria were isolated in least of samples (9.76%). The presence of T-2 toxin was detected in 75.61% of the samples, with concentration of 25.07 - 426.08 µg kg-1 (in average, 55.34 µg kg-1). The statistical insignificant negative correlation (r = - 0.05) was obtained between total fungal count and concentrations of T-2 toxin. In addition, a total fungal count and content of T-2 toxin in the samples were not above the maximum allowed levels, although the presence of species from genus Fusarium was found in 58.54% samples. These results indicated that the sanitary and hygienic conditions during the production of poultry feed in Serbia have been at satisfactory level. [ABSTRACT FROM AUTHOR]

Natural occurrence of Fusarium spp. and concentrations of mycotoxin deoxynivalenol (DON) in the grain of the winter wheat moderately susceptible to Fusarium head blight (FHB) has been studied. Grain samples were collected from wheat crops intended for human and animal consumption. All wheat crops were treated with fungicides before (a.i. flutriafol -- formulated as Fluoco, applied in dose of 0.5 l ha-1) and during the flowering phase of growing (a.i. thiophanate-methyl + epoxiconazole formulated as Eskorta plus and a.i. thiophanate-methyl formulated as Funomil, applied in doses of 0.75 and 0.5 l ha-1, respectively). Among of Fusarium species only F. graminearum, as a well known producer of DON, was identified. This fungus was identified in 15 of 19 samples (78.9%) with incidence in positive samples of 2 to 28% (average, 14.0%). Presence of DON was established in 13 of a total 19 investigated wheat grain samples (68.4%). In positive samples DON was detected in concentrations from 69 to 918 μg kg-1 (average, 478 μg kg-1). DON showed a significant and positive correlation at P≤0.05 with grain moisture content (r = 0.52*). Between the frequency of F. graminearum and concentration of DON and between the frequency of F. graminearum and grain moisture content, positive correlation was determined, but without statistical significance (r = 0.44 and r = 0.29, respectively). [ABSTRACT FROM AUTHOR]

Fusarium species have been isolated from over 100 plant species in Serbia. From the economic aspect, they have been and still are the most important for the production and storage of small grains and maize, and are exceptionally important for some other species. Total of 63 species, 35 varieties (var.) and 19 specialised forms (f. sp.) of basic species, particularly of F. oxysporum (4 var. and 12 f. sp.) and F. solani (7 var. and 3 f. sp.) were identified. Species F. langsethiae and F. thapsinum, recently identified, have been isolated from wheat and s o r g h u m seeds, respectively. F. graminearum is the most important pathogen for wheat, barely and maize, while F. poae is also important for wheat and barely. Furthermore, species of the section Liseola (F. verticillioides, F. subglutinans and F. proliferatum) are important for maize and sorghum. In recent years, species of the section Liseola have been increasingly occurring in wheat and barley. The June-October period in Serbia is the most critical period for quality maintenance of stored maize, as the abundance and frequency of fungi, particularly of toxigenic species of the genus Fusarium, are the greatest during that period. In general, there is a lack of data about fusarioses of industrial crops in Serbia. There are mere descriptions of specific cases in which the development of Fusarium species was mostly emphasised by agroecological conditions. The presence of recently determined Fusarium species in kernels of these plant species indicates their importance from the aspect of the yield reduction and grain quality debasement and the mycotoxin contamination. Root rot and plant wilt are characteristic symptoms of fusarioses for forage and vegetable crops, while pathological changes in fruits provoked by Fusarium species are less frequent. F. oxysporum and its specialised forms prevail in these plant species.

Effects of fertilisers on the grain yield (t ha-1) and the development of mycobiota, especially of the Fusarium species, in winter wheat kernels were observed. Fertilisers were applied in the following variants: T1 - 30m3 of slurry (pre-sowing treatment) and 25 m3 of slurry (top-dressing), T2 - 22.500 kg of manure (pre-sowing treatment) and 220 kg of urea (top-dressing), T3 - 300 kg of urea (top-dressing) and T4 - the control without application of fertilisers. The average wheat grain yield was the highest in the treatment T2 (6.9 t ha-1), then in T3 (6.3 t ha-1) and T1 (6.2 t ha-1), while the lowest wheat grain yield (4.3 t ha-1) was registered in the control (T4). Fungi of genera Alternaria (88.8-96.3%) and Fusarium (3.7-11.1%) were mainly isolated from all wheat kernel samples collected after harvest (T1-T4). Species of the genus Dreschlera were isolated in treatments T1 (0.3%) and T2 (0.2%). The species Stemphylium botryosum was isolated only in the treatment T1 (0.2%). F. graminearum (3.5-10.8%) was isolated from wheat kernels in all observed treatments, while F. sporotrichioides was isolated in treatments T1 (0.6%), T2 (0.5%) and T3 (0.3%). F. poae (0.3%) and F. subglutinans (0.2%) were isolated in the treatment T2, while F. graminearum was predominantly present in treatments T3 (10.8%), T1 (8.7%) and T2 (7.8%), and in the control T4 (3.5%). The obtained results point out that the application of urea affected the decrease in the intensity of Alternaria species infestation, but it also affected the increase of frequency of Fusarium species, especially F. graminearum, in comparison with the control and other treatments. Negative correlation was registered between the grain yield and the intensity of infestation of Fusarium species (collectively) and F. graminearum (individually).