Downy mildew on spring sown beans is a sporadic disease, hence routine spray applications are not justified. Monitoring weather at these sites can identify when crops in these locations are at risk from downy mildew, and enable growers to optimise use of fungicide treatments. Read further details of downy mildew forecast scheme.
Work funded by PGRO and carried out by CSL during 2000 - 2002 showed that spraying against the disease was most effective in the 10-14 day period prior to full flowering.
The forecasts on this page use locally collected weather (rainfall and air temperature) to highlight days when infection risk is heightened by cool and wet conditions. It is important to remember that these forecasts are aimed at the airborne stage of the pathogen's life cycle and so are most effective for fields which have not grown beans for some time. Fields that have grown beans in the past five to eight years will be at risk from soil borne infection which can attack plants very soon after emergence and certainly before flowering.
PGRO website: www.pgro.org