Taxonomy: Fungi, division ascomycete
Description: Spores are airborne and found in soil and water.
Distribution on the plant: Brown lessons on the lower leaves of the plant and darkening of the fruit of tomatoes.
Lifecycle: overwinter in crop residues and spores form when exposed to moisture and warm weather.
Determent to crops: Necrosis of leaf tissues and fruit
Monitoring remarks: Check for early signs on the low leaves of the crop. Monitor more frequently once the crop canopy has closed, and during periods of persistent rainfall.
Action threshold: Preventative fungicides recommended. Take curative action at early signs of the disease.
Control general remarks: Spray fungicides that are effective against Alternaria routinely.