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A total of 88 and 40 wheat samples collected immediately prior to harvest in 2005 and 2006, respectively, under different agroecological conditions, were studied in respect to the occurrence of Fusarium spp. and the production of fusariotoxins. The greatest number of samples was infected with species of the genera Fusarium (81.8 and 65.0%), and Alternaria (36.3 and 17.5%) with the intensity ranging from 9.4 to 84.0% in 2005 and from 23.4 to 80.6% in 2006. Out of 13 identified species belonging to the genus Fusarium, F. graminearum had the highest frequency (35.2 and 12.5%) and the intensity up to 67.2%, and 21.9%, in 2005 and 2006, respectively, followed by F. poae but only in 2005 (20.4%), and F. proliferatum in 2006 (19.7%). The natural occurrence of mycotoxins in positive samples varied from 37 to 331 ppb for zearalenone and from 31 to 125 ppb for diacetoxyscirpenol (DAS) and T-2 toxin. The concentration of mycotoxins amounted, on average, to 133.4, 61.0 and 45.7 ppb for zearelenone, DAS and T-2 toxin, respectively

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Broomrape has become one of the most important threats to the cultivated sunflower. New sources of resistance genes are needed to maintain sunflower production. The objective of this research was to evaluate accessions of wild sunflower species and their F 1 interspecific hybrids with cultivated sunflower for resistance to race E. Plant material consisted of 6 accessions of perennial species and 14 F 1 accessions between perennial species and cultivated sunflower as well as 42 accessions of annual species. Cultivated line JM8 was used as the sensitive check. Accessions were screened in the greenhouse in the season of 2008/09 and in a field trial during 2009. Plants were grown in the infested soil and evaluated for reaction at the end of the vegetation. The cultivated check was susceptible in the greenhouse and in the field trial. The annual species showed varying resistance with H. annuus and H. argophyllus as the most sensitive with an average of 6.6 and 8.5 broomrape plants per sunflower plant. Only 2 of the 7 H. petiolaris accessions were susceptible. H. neglectus performed well in the greenhouse with only one broomrape plant infecting one plant of the four tested accessions, but accession NEG1363 was infected in the field trial leaving NEG457 and 1183 as resistant. All accessions of perennial species except for an F 1 hybrid of DEC B and F 1 RIG 707 showed complete resistance. New potential sources of broomrape resistance genes have been found among wild species and their interspecific hybrids.

Eleven isolates of F. poae, originated from wheat grain at 9 locations mainly in Vojvodina, were encompassed by the present study. The greatest number of samples was collected in 2005, in which the climatic conditions favoured a more intensive occurrence of Fusarium ear blight of wheat. In order to determine toxicological potential of this species, cultures of the selected isolates were grown in liquid media (GPY and SPY) on a rotary shaker (180 revolutions min-1), at room temperature (21-26°C) for three days. Crude toxins were isolated from liquid culture filtrates of isolates by the use of ethyl acetate, while quantification of mycotoxins was done by the thin layer chromatography method. A liquid culture of the isolate GZ-LES (F. graminearum) was used as a control for the evaluation of the zearalenone biosynthesis potential. On the other hand, the liquid culture of the isolate KF-38/1 (F. sporotrichioides) was used as a control for both type-A trichothecenes (T-2 toxin and diacetoxyscirpenol - DAS). The obtained results show that F. poae, in contrast to F. graminearum, has no potential for the zearalenone biosynthesis. The presence of DAS was determined only in one isolate of F. poae (MRIZP-666), and in the control isolate of F. sporotrichioides (KF-38/1/R), that were grown in the GPY liquid medium. The T-2 toxin was detected in the isolate MRIZP-666, grown in both media, and in the isolates MRIZP-37 and MRIZP-860, cultured in the GPY and SPY liquid medium, respectively. The control culture KF-38/1/R (F. sporotrichioides) produced the T-2 toxin at the concentration of 4,000 μg L-1. According to the gained information, it can be concluded that the potential of F. poae for the type-A trichothecene biosynthesis was low, as the concentration of DAS or T-2 toxin did not exceed 80 μg L-1 or 240 μg L-1, respectively