Short-distance dispersal of wheat rust spores by wind and rain

摘要

After a brief description of the biophysical environment of diseased plants, mechanisms of short-distance dispersal of wheat rust spores by wind and rain are reviewed. Wind, and especially intermittent gusts, is the main agent of removal and transport of spores. Whereas wind does not seem to limit the process of short-distance dispersal, the effect of rain events is more complex. Laboratory and field experiments have shown that rain events enhance spore removal from sporulating lesions. Rain events also scrub airborne spores and deposit them onto susceptible plants. Extended or violent rain events, however, may finally wash off spores already deposited on leaves and be detrimental to the spread of disease.