Causal Agent: 

Fungus (Cercospora papayae)

 

Characteristic Symptoms:
 
Tiny black dots on fruit that eventually enlarge to about 3 mm in diameter.
   
Spots are superficial, slightly raised and do not develop into a fruit rot.
   
Actual damage to fruits is minor except its impact on their appearance and marketability.
   
Leaf spots are irregularly shaped, grayish-white in color and 1 to 5 mm in diameter.
   
Conditions for Disease Development:
 
The disease is common in humid tropic and subtropical regions.
   
The pathogen survives between crops on crop debris and weeds of the cucurbit family.
   
Conidia/spores are air-borne and are disseminated by wind, rain splashes, tools/implements and field workers.
   
Infection requires free water and is favoured by temperatures between 26-32°C, in which the disease develops rapidly with new infections occurring every 7-10 days.
   
Management and Control:
 
Maintain good field sanitation as the disease is most common in poorly maintained unsprayed papaya fields in wet area. 
   
Protective fungicide sprays of  mancozeb (e.g. Attain M-80Ⓡ, Achem Mancozeb 80 WPⓇ, Micron 80 WOⓇ, VanzebⓇ)and copper-based fungicides (e.g. Cupravit®, Super BlueⓇ, Vitigran blueⓇ, FunguranⓇ, KocideⓇ, Hydroxide superⓇ) at 14-28 days, depending on rainfall have been shown to be effective in controlling this disease.
 
References:
http://www.extento.hawaii.edu/kbase/crop/type/c_papa.htm

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