Management for early and late leaf spot in peanut

Fungicides that control early and late leaf spot in peanut

  • chlorothalonil
  • tebuconazole
  • tebuconazole + prothioconazole
  • propiconazole plus chlorothalonil
  • propiconazole plus trifloxystrolin
  • tebuconazole plus trifloxystrobin
  • azoxystrobin
  • pyraclostrobin
  • fluoxastrobin
  • boscalid

Many populations of leaf spot pathogens appear to be insensitive to tebuconazole. Performance of tebuconazole can be improved by mixing it with 12 to 16 oz. chlorothalonil. Tebuconazole can also be mixed with thiophanate methyl.

Early leaf spot in peanut

Cercospora arachidicola is a fungal ascomycete plant pathogen that causes early leaf spot of peanut.

Peanuts (Arachis hypogaea) originated in South America and are cultivated globally in warm, temperate and tropical regions.

All cultivars of peanuts are equally susceptible to peanut fungal pathogens; however, C. arachidicola is an economically important peanut pathogen and is responsible for significant economic losses in the peanut industry, more specifically in the Southeastern, Eastern, and the Southwestern United States.

Early leaf spot of peanut can drastically reduce yields, leading to economic downturn of the peanut crop economy.

Annual crop losses in the United States range anywhere from less than 1% to greater than 50% depending on disease management and treatment.

early leaf spot – close-up of conidia (seen as silvery, hair-like areas on the spot)
Cercospora arachidicola (early leaf spot pathogen)