If the crop was irrigated at 65 SWT until 10 days after bloom initiation, then at 30 SWT for the remainder of the season, yield losses were somewhat greater than at 65 SWT for the entire season, but much less than when irrigated at 30 SWT throughout the season. These and the above data were developed on kidney beans. Measuring total water applied to a field provides a simple way to determine if a fungicide is likely to provide an economic return. Benlate and Topsin M both provide good disease suppression. White mold can look so bad in treated fields that producers may not know if the treatment was effective unless they leave an untreated check strip which they harvest separately and get a separate weight slip from the elevator.
Fungicides are effective when applied by air or by ground.
The best time for application is early bloom or within four days of early bloom. Broadcast spraying at 100 psi, although less effective, has provided reasonable disease suppression and yield increase. Research data has consistently shown better yields with 22-inch row spacing as long as white mold has not been too severe. The closer rows may result in a thicker canopy, favoring white mold. It is almost impossible to effectively use drop nozzles on 22-inch rows.