Peanuts are a very popular commodity, with annual U.S. production well above 2 billion pounds. But peanut varieties are plagued by pests like the peanut root-knot nematode and diseases like tomato spotted wilt virus (TSWV).

While certain peanut varieties exhibit resistance to either the microscopic worms or the TSWV pathogen, Tifguard is the first variety that has resistance to both. It is the product of research by plant geneticist C. Corley Holbrook in the ARS Crop Genetics and Breeding Research Unit at Tifton, Ga.; plant pathologist Patricia Timper in the ARS Crop Protection and Management Research Unit, also at Tifton; and University of Georgia collaborators Albert Culbreath and Craig K. Kvien, in the College of Agriculture and Environmental Sciences.

Tifguard was developed by hybridizing a TSWV-resistant cultivar with a nematode-resistant cultivar. Field tests for resistance to peanut root-knot nematode were conducted at two Georgia farms in TiftCounty that were heavily infested. In testing for TSWV-resistance, Tifguard plants were grown in plots at one of the TiftCounty farms that also displayed severe TSWV problems.

Not only did Tifguard exhibit higher resistance to TSWV, it also produced higher yields than standard check cultivars when grown in fields with little or no nematode pressure. And because of its high level of resistance to both TSWV and root knot nematode, Tifguard had significantly higher yields than all other varieties when grown in two locations with high pressure from both pathogens.

For these reasons, Tifguard should be particularly valuable to peanut growers who have to deal with both root-knot nematodes and TSWV. It was released in 2007 and is currently in seed production. Seed for farmers should be available by the 2009 planting season.

ARS is the U.S. Department of Agriculture`s chief scientific research agency.

Copyright 2008 ARS USDA