A comparison of seasonal changes in deposition of spores of Erysiphe graminis on different trapping surfaces

Vertical sticky cylinder traps were as useful as a volumetric trap for detecting seasonal changes in numbers of Erysiphe spores from barley crops. Changes in spore catches by both traps also resembled changes in numbers of pustules developing on initially healthy barley seedlings exposed in the same crop. Seasonal changes in catches on cylinders exposed at some distance from any crop differed from those on cylinders just above barley crops.

Cylinder traps are cheap, simple and quicker to scan than volumetric traps and seem likely to be acceptable alternatives to them for much work on cereal mildew and other air‐dispersed pathogens, particularly for routine trapping at many sites.