PEANUT CULTIVARS and SPOTTED WILT
Use of moderately resistant cultivars is the "cornerstone" of an integrated package for managing spotted wilt of peanut. Several new cultivars have been released in 2002, and more new cultivars should be available in the next two years. Although many factors must be considered when choosing a cultivar, resistance to spotted wilt definitely should be considered. The following list is a summary of the relative resistance of most of the runner-type cultivars grown in Alabama, Georgia, and Florida, as well as a few virginia-type cultivars. The relative resistance level of these cultivars indicated below is based on various field studies and observations for periods of time that vary with the individual cultivars.

CULTIVAR SUSCEPTIBILITY
(Relative resistance decreases as you go down the list.)
  • MODERATELY RESISTANT III
  • DP-1

  • MODERATELY RESISTANT II
  • C-99R, Carver, Hull, Georgia 02C

  • MODERATELY RESISTANT I
  • Andru II, FL MDR 98, Georgia Green, Gregory, Norden, Southern Runner, VC-2, Virugard

  • INTERMEDIATE III
  • Georgia Hi-OL

  • INTERMEDIATE II
  • AT-201

  • INTERMEDIATE I
  • Andru 93, GK-7, NC-V11, NC 12C

  • SUSCEPTIBLE II
  • Perry

  • SUSCEPTIBLE I
  • Florunner, Flavorunner, SunOleic 97R

No peanut cultivar is immune to TSWV. However, a few varieties have consistently demonstrated moderate levels of resistance. In addition to resistance, (reduced disease incidence), some varieties appear to have some degree of tolerance (reduced severity in infected plants) as well. Higher levels of resistance and tolerance are anticipated since peanut breeding programs are now evaluating potential new varieties for response to TSWV.

The new cultivars DP-1 and Georgia 02C have shown very promising improved resistance to TSWV compared to Georgia Green. Both of these cultivars have resistance to other pathogens as well. DP-1 has moderate resistance to early and late leaf spot pathogens, and Georgia 02C has moderate resistance to Cylindrocladium black rot.

Another new cultivar, Georgia 01R, will be available on a very limited basis in 2003. It also has significantly better resistance to TSWV than Georgia Green, and resistance to other pathogens as well. More information should be available on it for the 2004 season.

For more information on any of these or related topics, feel free to contact Albert Culbreath by phone (912) 386-3370, fax (912) 386-7285 or email (spotwilt@tifton.uga.edu).