Management of Soybean White Mold
In the 1996 field season, white mold was prevalent in many Iowa soybean fields at much greater levels than in 1992 and 1994. This outbreak may be attributed to the high moisture (rain and heavy dew) and cool temperature in August. Compared with 1994, the disease differences were 1) a greater number of severely infested fields with sizes ranging from 50 to 100 acres have been observed, and 2) the disease occurred further south. Although the disease was observed in counties as far south as hwy 34 in 1994, no severe damage was reported. This year severe infestation occurred in a number of soybean fields along hwy 34. Our data indicates that the disease is here to stay, and very likely to increase in the future if we do not manage it properly. Two strategies are proposed to manage the disease: prevent the introduction of the pathogen into noninfested soybean fields, and control the build-up of the pathogen in fields where the pathogen has been introduced.