Comparison of the effectiveness of standard and drift-reducing nozzles for control of some winter wheat diseases

Distribution of prothioconazole and tebuconazole between wheat ears and flag leaves following fungicide spraying with different nozzle types at flowering

“…The better ear coverage achieved with the sideward‐spraying nozzle types and configurations has long been studied . Different types of nozzle have been tested with specific spraying parameters such as the droplet size produced by the fans, the amount of spray liquid applied and the speed and pressure of spraying . Similarly to the present findings obtained by the use of WSPs and tracer dye, the better ear coverage after sideward‐spraying was clear cut, although the variation in the spraying parameters, environmental factors and the epidemic levels made it difficult to draw far‐reaching conclusions .…”

“…Wolf and Caldwell concluded that a double nozzle configuration increased the ear coverage, and an air‐induced nozzle with a 60° angle was superior to a vertically‐spraying conventional nozzle and a 30° angle nozzle configuration, but they failed to demonstrate a significant effect on the FHB disease severity with tebuconazole. Vajs et al also reported that a sideward‐spraying double flat‐fan nozzle was superior to the vertically‐spraying standard and drift‐reducing nozzles in controlling FHB.…”

“…In contrast, in the experiments of Hooker et al , the Turbo FloodJet nozzle with its coarse droplets achieved the highest efficacy. In their comparison of standard and drift‐reducing nozzles for the control of wheat diseases, Vajs et al found in a 3 year experiment that standard nozzles permitted a better control of FHB than that attained with drift‐reducing nozzles.…”

Changes in field dose–response curves for demethylation inhibitor (DMI) and quinone outside inhibitor (QoI) fungicides against Zymoseptoria tritici, related to laboratory sensitivity phenotyping and genotyping assays

“…Mutant strains that have low or moderate resistance factors (mutant strain EC 50 divided by wild‐type EC 50 ) are likely to remain sensitive to doses near the maximum permitted field dose, but be insensitive to lower doses, resulting in an observed reduction in field dose–response curvature. The effect on curvature is complicated by the great diversity of insensitive variants and by variation in the deposition of dose at different points in crop canopies . That the asymptote of DMI response curves was also decreasing, more especially in curative situations, suggests that a proportion of the Z. tritici population may now be beyond control at field rates of DMI application.…”

Effect of spraying speed on head coverage of winter wheat with fungicide, occurrence of Fusarium head blight and deoxynivalenol, yield and grain quality

“…Ruden et al (2005Ruden et al ( , 2007 also stated that most nozzle types ensure better coverage of the front part of a head. Several authors determined that the front and rear parts of a head have better fungicide coverage when single backward-angled nozzles, symmetric double flat fan nozzles or as symmetric double flat fan nozzles are used (Miller et al 2002;Parkin et al 2006;Vajs et al 2008;Knewitz and Koch 2010). Hooker et al (2004) stated that both standard and new spraying technologies allow for a 10% coverage value on wheat heads.…”