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Four wheat cultivars with different levels of tolerance to Fusarium head blight (FHB) were grown in small plots and were inoculated with spores of Fusarium fungi during the anthesis. The harvested grain was cleaned by a special cleaner which separated it in 4 size fractions: F1 ->2.4 mm, F2 -2.0-2.4 mm, F3 -1.8-2.0 mm, F4 -<1.8 mm. These were further divided manually in four sub-fractions according to the rate of FHB symptom expression, i.e. grain without any visible symptoms, grain with changes in colour without changes in shape, grain with changes in colour and moderate changes in shape or size, and heavily infected malformed grain. Deoxynivalenol (DON) content in grain of different fractions was determined by high-performance liquid chromatography with UV detection (HPLC-UV) analysis. Comparisons between initial DON content before cleaning and DON content in individual fractions after cleaning were made. The cleaning efficacy (rate of DON content reduction) due to the cleaning and separating of grain in size fractions was higher in semi-tolerant and susceptible cultivars than in FHB tolerant cultivar. Due to the low cleaning efficiency, cleaned grain of tolerant cultivar (without any symptom of FHB), contained twice more DON (870-1350 µg kg -1 ) than cleaned and apparently healthy grain of semi-tolerant cultivar (160-570 µg kg -1 ); its DON content was comparable to that of the susceptible cultivar (905-1140 µg kg -1 ). Our results indicate that FHB tolerant cultivars may contain a high proportion of grain which is apparently healthy, but contains excessive DON levels. Such tolerant cultivars can contribute a lot to minimisation of yield loss caused by FHB, yet they may present a potential health hazard of organic whole-grain flour produced in non-industrial grain processing systems.

Trials were carried out in apple orchards of two different training systems to assess the relationship between spray drift and parameters of spraying with an emphasis on the sprayer's travel speed when applying different solutions, such as pesticides or fertilizers, onto the apple trees. The assessments were based on the following factors: per cent of spay drift, two sprayers (axial-and radial-fan sprayer), two training systems (super spindle and modified slender spindle), spray droplet size (fine or coarse droplets) and the sprayer's travel speed (5 vs. 10 km h -1 ). The studies were conducted in the spring and summer seasons under similar external weather conditions to test any seasonal effects that might occur. In this paper, all tested factors and interactions were found to have a significant effect on the spray drift during spray application. For instance, the increase in sprayer speed reduced the spray drift percentage. Other factors, such as sprayer type (axial fan and radial fan) and tree training system, had an impact on spray drift as well.