BBC LABORATORIES
Agricultural & Environmental Microbiological Services
[ Pathogen Inhibition Assays ]
What are pathogen inhibition assays?
These assays are a screening technique to determine if biological agricultural products, compost, compost teas, and soils contain organisms that have the potential to actively inhibit the growth of specific plant pathogens. Some of the types of microorganisms that inhibit plant pathogens include: Pseudomonads, Actinomycetes, Fungi and Bacillus sp.
Microbes have various modes of action for the inhibition of plant pathogens. Inhibition can occur by the microbe's production of antibiotics and other antimicrobial compounds, by the microbe's successful competition for nutrients, by the organism's preferred colonization sites on roots, by their induction of resistance to pathogens in host plants, and/or by acting as parasites or predators to pathogens.
What Pathogens can be tested?
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.
Many common plant pathogens can be tested with this analysis. Typical pathogens include(others also available):
| Alternaria (leaf spot) | Phymatotrichum (Texas root rot) |
| Armillariella (shoestring root rot) | Phytophthora (crown and root rot) |
| Botrytis (gray mold) | Pythium (root rot) |
| Colletotrichum (Anthracnose) | Rhizoctonia (stem and root rot) |
| Drechslera (leaf spot and melting out) | Sclerotinia (Sclerotinia rot) |
| Erwinia (soft rot, blight) | Sclerotium (southern blight) |
| Fusarium (root rot) | Verticillium (wilt) |
| Gaumannomyces (Take-all patch) |
Please contact the laboratory for an updated list of plant pathogens in our culture collection.
Advantages of Pathogen Inhibition Screen
- -Does not require microbial isolation or identification in compost or product
- -Ability to test against specific pathogens of concern
- -Allows for future isolation and cultivation of selected microbes
- -Can be used to assist in the detection of product or compost application rates