How is that stand?

The watermolds, Pythium or Phytophthora, affecting soybeans

Some soybeans have been planted and issues have already been reported.  The most common symptom is spotty areas around the field with large skips or limited emergence.  Take a garden trowel and dig up a few places and try to find the seed that was placed there.  Here is a review of the seedling disease issues that are common most years in Ohio.

1. The Watermolds, Pythium and Phytophthora, are very common on poorly drained, high clay soils.  These pathogens love wet soil conditions.  The few places in the state where saturated soil conditions have occurred are the very typical.  Look for any shade of brown or tan on the seedling root or hypocotyl, the area right behind the deep green cotyledon.

2. Rhizoctonia is another foe of seedlings.   Fluctuating conditions, dry to wet can sometimes favor this pathogen.  This is a brick corky red color, close to a brick house on the lower stem and the roots can range from light brown to dark brown in color. 

3. Fusarium graminearum or other Fusarium spp. – Fusarium tends to be bright pinkish-red and fluffy.  We have found this most often in fields with a high level of corn residue. 

There are other pests that will feed on the seeds and seedlings.  Seed corn maggot is one, slug damage is another.  Missing plants or plants with holes in leaves, cotyledons will appear differently than the sunken, rotting tissue of diseases.

Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.

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