Pepper spot of perennial peanut
Sep 14, 2012 6:57 AM
Fungal causal agent: Leptosphaerulina crassiasca
Symptoms: a) Pepper spot: Minute dead spots dark brown to black, less than 1 mm in diameter. These occur in a random pattern on both sides of leaflets. May be confused with some chemical burns. Not a common symptom. b) Leaf Scorch: Often in tip or margins of leaflets. First sign is yellowing and then death (necrosis) of infected area. Necrotic area (1/4 to 3/4") surrounded by yellow halo often with dark circular area or concentric rings in dead tissue. stem lesions are black and may be over 6 inches long. b) Leaf Scorch can be a serious problem in landscape and greenhouse-produced peanuts. The HOST RANGE: Peanut, perennial peanut.
Management: Canopy and water management helps in reducing disease symptoms of pepper spot and leaf scorch. Fungicides can be applied during optimum conditions for disease occurrence and spread. Check http://premier.cdms.net/webapls/formsloginRef.asp?/webapls for current labels in ornamental production.