Isolate from Plant Roots

• 1). Cut pieces of lesions from plant root tissue two square millimeters in area. Place the samples in plastic bags, and then store the samples at 4 degrees Celsius.
  
  
• 2). Wash the root samples under tap water, and plate root samples with potato carrot agar media for growth. Corn meal agar media can also be used.
  
  
• 3). Incubate the cultures at a temperature of 25 degrees Celsius in a dark place for 48 hours.
  
  

Isolate from Soil Samples

• 1). Take a soil sample from an area known to be infested with Pythium.
  
  
• 2). Pour the soil sample through a mesh screen sieve with a pore size of .84 millimeters.
  
  
• 3). Dilute the filtered soil sample using .3 percent sterile water agar. Use a dilution ratio of one part sample soil to 50 parts water. Combine 1 milliliter of this dilution with a selective media containing corn meal agar in a petri dish.