Tall fescue established as a preplant cover crop may help protect peach trees from nematodes that attack their roots, say USDA-ARS scientists in Byron, GA, and Beltsville, MD.

They evaluated the grass as a tool for alleviating a problem that can severely stunt peach-tree growth in the Southeastern U.S. They point out that growers traditionally fumigate soils before planting and then use nematode-resistant root stock. But fumigation is expensive, and many growers have difficulty fumigating at the right time because of conflicts with other crops.

The researchers tested four tall fescues and found that MaxQ, a novel-endophyte variety, is effective against most nematode species.

“Our studies demonstrated that two of the nematodes – M incognita and M. hapla – can’t reproduce on MaxQ,” reports Susan Meyer, plant pathologist at the USDA-ARS Nematology Lab in Beltsville. “Meloidogyne javanica has a low level of reproduction on MaxQ, but M. arenaria can reproduce on it. This shows that MaxQ may well have potential as a preplant control strategy for M. incognita and M. hapla in Southeastern and Northeastern areas. Using this tall fescue as a preplant cover-crop treatment may allow growers to reduce the use of chemical nematicides.”

“Preliminary data indicates that trees planted after a one- or two-year MaxQ grass cover crop and trees planted in fumigated soil are significantly larger than trees in unfumigated soil,” adds plant pathologist Andy Nyczepir at the agency’s Southeastern Fruit and Tree Nut Research Lab in Byron.