Can "good fungi" help plant defenses?

March 3, 2016 11:45 AM
Blog Post

Many of you know about naturally-occurring entomopathogens in the soil that can kill or suppress insects. Bacillus thuringiensis (Bt) is a well-known example of a bacteria that kills insects, and was eventually included in plants as a transgenic protein. My Ph.D. student, Eric Clifton, spent his whole master's degree finding entomopathogenic fungi (EPF) in Iowa. Not surprisingly, he found lots of different EPFs in corn and soybean fields. You can read about his thesis results here

Today, I followed Eric around the lab while he is starting a new research project. He is interested in learning about how EPFs can help induce plant defenses. This is a relatively hot topic, as you can imagine giving plants a "vaccine" of sorts to help fight off pests like insects and nematodes sounds too good to be true. A good, but technical, paper that reviews induced plant defenses can be found here. Eric is looking at two common EPFs for this study, Metarhizium anisopliae and Beauveria bassiana.

Eric's plant inoculation is a multi-step process, but basically he creates a fungal slurry and coats soybean seeds. It kind of reminds me of a seed treatment. He is measuring how many soybean aphids are produced on EPF-coated seeds versus untreated seeds. So far, the results are showing some induced plant defenses from this EPF seed treatment. We have so much to learn, but thought you might find this idea interesting. 

Metarhizium anisopliae sporesBeauveria bassiana

Dry spores of Metarhizium anisopliae (left) and Beauveria bassiana (right).

Sterilized soybean Fungal slurry with soybean seeds

Sterilized soybean seeds (left) are soaked in a fungal slurry (right) for 24 hours before planting. 

Author: 

Erin Hodgson Associate Professor

Dr. Erin Hodgson started working in the Department of Entomology at Iowa State University in 2009. She is an associate professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated pest management (IPM) for field crops. Dr. Hodgson's curre...