A network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests.
PestNet is a network that helps people worldwide obtain rapid advice and information on crop protection, including the identification and management of plant pests. It started in 1999. Anyone with an interest in plant protection is welcome to join. PestNet is free and is moderated, ensuring that messages are confined to plant protection.
September 2010. Photos of peppers with spots were sent from Bella Vista, province of Corrientes, Argentina. The spots look like blisters, with the skin forming a light or bright halo with a small necrotic centre. No fungi or bacteria were isolated.
Phytotoxicity is suspected from chemicals or detergents, but the leaves do not show any symptoms. Also, the symptoms do not occur on all fruits and, as seen in the photographs, the spots are found mostly on one side – the shoulder – of the fruit.
A member thought the spots suggested a sucking insect with a toxic response to its saliva. Is the green vegetable bug Nezara viridula present? Look for adults, particularly at night, or brightly coloured juveniles, often clustered together on the fruit.
Another member said that the symptoms on the photo resemble Ghost spot, which is normally caused by the fungus Botrytis cinerea. Similar symptoms have been seen on capsicum or tomato fruits (photo, lower right) mainly on green fruits, during cooler and moist weather conditions.
A good paper on this was published by Williamson et al. (2007) Molecular Plant Pathology 8(5): 561???580.