BBC LABORATORIES
Agricultural & Environmental Microbiological Services

What are they?

Mycorrhizae, literally translated, means "fungus-root." Mycorrhizal fungi, known as "VAM" (vesicular-arbuscular mycorrhizae) or "AMF" (arbuscular mycorrhizal fungi), are a group of soil fungi that colonize plant roots. Most terrestrial flowering plants form a relationship with mycorrhizal fungi, and the relationship is generally beneficial to the plant.

Why are they important?

Mycorrhizal fungi rely on their plant hosts for organic carbon, and in return they may help the plant with nutrient uptake and drought resistance. Some mycorrhizal relationships have been documented to help prevent plant disease.

Three kinds of mycorrhizal testing

• Root colonization - This test is performed on plant root samples and will tell you how much mycorrhizae are growing in a sample of roots, expressed as percentage of roots colonized.
• Spore enumeration - This test is performed on soil, compost, or manufactured inoculum products and will tell you how many mycorrhizal spores are present per gram or milliliter of sample.
• Infectivity potential - This test is performed on soil or manufactured inoculum using specific plants to determine the number of infective (colonizing) mycorrhizal units available.