By Sharon Durham
A new peanut variety developed by Agricultural Research Service (ARS)
scientists may help farmers in their battle against two key peanut
problems.
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.

[www.ars.usda.gov]