This is, perhaps, one of the most valuable diagnostic tools available to growers. It was developed by and is exclusive to 20/20 Seed Labs Inc.
The table below is an outline of the diseases that 20/20 Seed Labs Inc tests for in a Fungal ScreenTM. The points listed below are a guide to assist with interpreting the results from a Fungal ScreenTM analysis. Click on the links to view the images.
Pathogenic Fungi – Common Name / Symptoms
Saprophytes or Weak Pathogens Commonly found pathogens that can become more aggressive during delayed harvest and through mechanical damage. These fungi can cause seed discoloration resulting in lower seed grades.
Storage Molds These are found on the seed surface and can damage improperly stored seeds.
- The results can be used to determine the seed treatment that will provide the best control of the pathogens listed.
- The results may also be used for deciding that the level of infection may be too high for adequate control with a seed treatment and a new lot of seed should be sourced.
- The 5 pathogens listed above are the most harmful of the 10 seed borne diseases. It isn’t uncommon to see these at low levels such as 0.5% to 2.0%.
- When Fusarium graminearum is at 0.5% or higher, planting of the seed should be avoided unless the disease is already established in the area and/or the field.
- When infection levels of any one of these diseases is higher than 8% infection, seed treatments may not provide the necessary control of the pathogen.
- If three or more of these five pathogens total more than 12%, control by seed treatments may not be sufficient.
Saprophytes or Weak Pathogens
- These three seed borne disease have a much wider range of infection levels.
- Alternaria is very widespread and is usually in the 20% to 50% range. May be higher in wet years.
- Cladosporium is usually in the 10% to 25% range. May be higher is wet years.
- Epicoccum is usually in the 5% to 20% range.
- These molds tend to present a problem in warm, high humidity condition where they will quickly multiply and cause degradation.
- Aspergillus is typically less than 2% infection.
- Penicillium is typically less than 2% infection.