Papaya Ringspot Virus
Papaya ringspot virus (PRSV, potyvirus)
Symptoms
Mosaic mottling and distortion of young leaves, with characteristic oily concentric ring spots on the fruit and dark streaks on the petioles and stem. Fruit quality and yield collapse and trees decline.
Prevention
Plant resistant varieties or virus-free seedlings and keep new plantings far from old infected ones. Control the aphid vectors and rogue out infected trees early.
Treatment
Organic
There is no cure. Slow aphid-borne spread with reflective mulch and neem oil, and remove infected trees to protect the rest of the planting.
Chemical (last resort)
No chemical cures the virus, and insecticides do not stop aphid transmission well because spread is rapid. Focus on roguing and vector deterrence rather than spraying.
Affects 1 crop
Sources
MARDI Papaya Production Guide; DOA IPM Manual