Seed Rots and Seedling Blights
Select high quality (germination
   85%), vigorous, disease-free
   seed of an adapted cultivar.
Plant at proper depth and
   spacing.
Select adapted cultivars with
   either race-specific or rate- 
   reducing resistance (field
   tolerance) to Phytophthora for
   fields with a potential for this
   disease.
Treat seeds and/or soil. (Seed
    treatment fungicides may be
    effective where pod and stem
    blight or seed-borne diseases 
    are involved, or when planting
    under unfavorable conditions.)

Root and Stem Diseases
Select adapted cultivars with
   good genetic resistance or
   tolerance to the diseases.
Rotate soybeans with non- 
   legume crops. (Crop rotations 
   of longer than two years are
   suggested in fields where 
   brown stem rot, charcoal rot or
   Sclerotinia stem rot were severe
   in the previous soybean crop
   and resistant varieties are not
   available.)
Consider solid (narrow rows, 
   10 inches or less) seeding. May
   increase the incidence of
   Sclerotinia stem rot, but could
   reduce the severity of charcoal
   rot, especially in hot, dry years.
Maintain adequate, balanced 
   soil fertility levels.
Harvest early to reduce pod and
   stem blight development,
   especially in fields being grown
   for seed.

Foliar Diseases
Rotate crops. (Generally one
    year out of soybeans is
    sufficient.)
Select adapted, disease-free
    cultivars with resistance to the
    diseases of concern.
Consider foliar fungicides.
    (They may provide control of
    brown spot, downy mildew or
    Cercospora blight, but they are
    generally only economical in
    seed production fields.)

Seed Diseases
Rotate crops. (Usually one year
    is sufficient.) 
Select high-quality, disease-free
   seed of an adapted cultivar.
Consider foliar fungicides. 
   (They may provide control of
   these diseases, but are 
   recommended mainly for seed
   production fields.)
Harvest early to reduce pod and
   stem blight development,
   especially in fields being grown
   for seed.

Gray leaf spot on corn.

Virus Diseases
Select adapted varieties with
   genetic resistance or tolerance 
   to important viral diseases.
Control broadleaf weed hosts 
   of the viruses and volunteer
   soybeans.
Use high-quality, disease-free
    seed.

White mold on soybeans.

Nematode Diseases
Select adapted cultivars with
    good resistance or tolerance to
    the soybean cyst nematode.
    (This may require a race test to
    identify the predominant trace 
   of cyst nematode present in an
    individual field.)
Rotate crops. (Depending on 
   the population of the soybean
   cyst nematode in a given field,
   a 3-7 year rotation that includes 
   a combination of non-host 
   crops like corn, sorghum, small
   grains, and soybean cultivars 
   resistant to the nematode may
   be necessary. A 3-year or
   longer rotation with non-host
   crops or resistant cultivars is
   suggested to keep the nematode
   population at sub-economic 
   levels.)
Alter date of planting. (Some
   research from the southern U.S.
   has shown that delayed planting
   may reduce the level of 
   nematodes initially present, and
   may be beneficial in some areas
   of the north central region. 
   Northern areas of the north
   central region may not benefit
   from this.)