Friday, May 26, 2017
University of Hawaii at Manoa
University of Hawaii System
College of Tropical Agriculture and Human Resources
Welcome to UH-CTAHR's "Pic-a-Papaya" Citizen Science Project

Citizen Scientists: We invite you to help CTAHR Researchers Scot Nelson and Richard Manshardt "Pic-a-Papaya."

What: We are asking you to help us survey papaya plant populations in the Honolulu area for papaya ringspot disease (PRSV) and for plants with genetically engineered resistance to PRSV.

How: Download and use the free Pic-a-Papaya app for smartphones to snap pics of papaya plants and send them to Drs. Nelson and Manshardt for diagnosis of PRSV. Each plant will be assessed a value of healthy or diseased and its GPS coordinates mapped to a location in Hawaii. Users of the app can view the map to see the distribution of infected plants (see the Map page).

 --> Download the "Pic-a-Papaya" app <--
iPhone | Android


Why? PRSV is a damaging disease of papaya that used to be common in Honolulu during the 1960s through the early 2000s. Today, there are still many healthy papaya plants in Honolulu, and PRSV seems to be relatively rare.

One explanation for the reduced incidence of PRSV in Hawaii is that papayas with GE resistance to PRSV have been grown commercially in Hawaii since 1998. 

We want to know to what extent the PRSV-resistant GE plants are present in Honolulu neighborhoods.

Therefore, we need your help to send up photos of your papaya plants in Honolulu for our survey. Find a papaya plant in y our yard or neighborhood, anywhere in the Honolulu metropolitan area (Hawaii kai to Kapolei). The plant can be big or small, with fruits or without. Please: NO COMMERCIAL PLANTS and be careful not to trespass. Be respectful of others' property.

Two screens for the Pic-a-Papaya app for iOS and Android devices

Go to the appropriate link on your iPhone or Android smartphone and download the free “Pic-a-Papaya” app.


Follow the instructions in the “Pic-a-Papaya” app for taking photos of different aspects of your papaya plant. If you have multiple plants, complete all photos for the first plant and press SEND, before moving on to the next plant, and so on. When you press "Submit", the photos will come to us at UH Manoa, along with your plant’s GPS coordinates (latitude & longitude).

We will use the photos to determine whether your plant has symptoms of PRSV. If we need more information, you may receive an e-mail or text message from us on your smartphone.

The GPS coordinates will let us plot the distribution of diseased and healthy plants on a map of the Honolulu area.  The map will be accessible to all “Pic-a-Papaya” app users. 

You can watch the map evolve!

Visit the "Map of Data" page on this site to see the updated map

Home   |   Papaya Ringspot   |   Papaya: Science and GE   |   Submit Samples for GUS   |   GUS assay   |   Map of Data   |   Contact
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