Fighting Farmland Pollution with Fungi

MnDRIVE-sponsored research by Laura Bender

Kyle Wong (writer)

With support from the MnDRIVE Environment Initiative, doctoral candidate Laura Bender harnesses the power of soil fungi to help plants absorb pollutants

To ensure a healthy crop, Minnesota farmers carefully track soil health, nutrients and the quantity of water flowing through their fields. Since 2015, Minnesota’s Buffer Law also requires farmers to tend to historically overlooked land along the edge of these fields. The law mandates a 50-foot buffer along farm fields bordering public waterways, including irrigation and drainage ditches, to help reduce contamination from farm runoff. Instead of corn, soybean and other cash crops, buffer zones are full of perennial plants and trees adept at absorbing excess nutrients flowing from the fields. With financial assistance through environmental programs like the federal Conservation Reserve Program, farmers have both the mandate and the incentives to establish quality buffers. 

Like their commercial counterparts, plants in buffer zones naturally take up nutrients, but researchers like graduate student Laura Bender, hope to improve the process by focusing on fungi living beneath the soil. Soil fungi colonize the roots of buffer plants to form a symbiotic, or mutually beneficial, relationship. “These relationships help plants take up pollutants that would otherwise escape to the waterways, but soils are often degraded through decades of tillage and fertilizer application and compaction,” Bender notes. “The fungi communities that are naturally present in soil are often degraded or absent.” Supported by a 2018 MnDrive Environment seed grant, Bender works to restore those fungal communities to strengthen buffer plants and keep Minnesota waters clean. Read more.