Department of Agriculture

Papaya Ringspot Virus Reappearance Confirmed in Several Areas on Maui

Honolulu – Test results have confirmed that the Papaya Ringspot Virus (PRV) has reappeared in several locations on Maui after a report of possible PRV infection was reported last week by a homeowner in West Wailuku.

Since the report, agricultural specialists from the University of Hawaii’s College of Tropical Agriculture and Human Resources (CTAHR) and the Hawaii Department of Agriculture (HDOA) have been surveying areas on Maui and have identified several other residential locations in West Wailuku, Waikapu, Kihei, Pukalani and Makawao that appear to also have been infected by PRV. Surveys are still being conducted to determine the extent of the outbreak on the island.

PRV is a serious affliction of papayas that causes poor quality, ring-spot-blemished papaya fruits, and the eventual death of the plant. The disease is transmitted from infected papaya plants to healthy plants by aphids. There is no cure for the virus. Agriculture officials are recommending that affected papaya trees be destroyed to help stop the spread of the disease on Maui.
Maui residents are asked to check their papaya trees for symptoms of the virus, which include yellowing of the top leaves, shoestring-looking leaves, water-streaking on the petioles (leaf stalks) and ringspots on the fruit (see photos). If residents suspect that their trees have PRV, they should call either HDOA’s Maui Office at 873-3555 or the CTAHR County Extension Office at 244-3242 for instructions.

Agriculture specialists from CTAHR and HDOA will be available to answer questions and provide information on PRV on Maui this Saturday, April 13, at Kaahumanu Shopping Center near Center Stage from 10 a.m. to 2 p.m.

In 1994, PRV appeared on the Big Island and proceeded to devastate the commercial papaya industry on that island, which grows about 90 percent of all papayas in the state. Researchers at CTAHR have developed a genetically modified papaya that was resistant to PRV and farmers have being using the disease-resistant varieties to manage the disease on the Big Island. CTAHR has plans to make available the disease-resistant varieties on Maui.

PRV made a brief appearance in 1974 in Happy Valley on Maui, but was eradicated on that island by 1975. At that time, only 100 trees within 400 acres were affected. PRV is widely established on Oahu and the Big Island. Kauai, Molokai and Lanai are the only islands that are not known to have the virus. HDOA will be establishing a quarantine on the movement of papaya plants from Maui to Kauai, Molokai and Lanai. However, papaya fruit and seeds may be transported. In the meantime, agriculture officials are asking the public not to transport papaya plants or plant parts from infected areas to non-infected areas.

Media interested in receiving color photos of PRV-infected fruit and trees via e-mail should call HDOA on Oahu at 973-9560.

Photos in PDF format are available by clicking here.