Providing practical information to help you protect your farm from biosecurity risks

Papaya pests

 

High priority exotic pests

The following pests are the exotic pests that pose the greatest threat to the Australian papaya industry. The climate of Australia’s papaya producing regions would allow each of these pests to survive, spread, and establish, should they be introduced, causing serious problems for producers.

Make sure that you and your workers are familiar with these pests and monitor your orchard regularly. Any suspicious plant pests or fruit symptoms that you have not seen before should be reported immediately to the Exotic Plant Pest Hotline on 1800 084 881, or to your state or territory department of agriculture.

More information on these pests are included in the fact sheets in the links.

These high priority exotic pests were identified through the development of the Industry Biosecurity Plan for the Papaya Industry. This document includes a complete list of exotic papaya pests and is available from Papaya Australia.

Papaya mealy bug

Papaya mealybug

Paracoccus marginatus. Photo by Peggy Greb, USDA Agricultural Research Service, Bugwood.org

 

 
  • Small yellow-white insect that feeds on the sap of papaya and numerous other plants
  • Feeding causes leaf chlorosis, leaf distortions and can cause early fruit fall
  • While feeding, the mealy bugs produce honeydew which encourages sooty mould to develop. This reduces the marketability of fruit
  • The papaya mealy bug occurs in southern and south eastern Asia, Central America, Mexico and Florida as well as some African countries
  • The pest could be introduced on plants and plant material from overseas and potentially people who have recently visited an infected papaya orchard

Fact sheet

Oriental fruit fly complex

Oriental fruit fly complex

Bactrocera papayae, B dorsalis and B carambolae. Photo by Scott Bauer

 

 
  • Includes Oriental, papaya and carambola fruit flies
  • Found in Asia, Papua New Guinea, the Pacific and South America
  • Adults 6-8 mm long with a narrow brown band along the edge of the wings
  • Abdomen has a black T-shaped mark, which is similar to a number of other endemic species
  • Larval feeding can result in rotting of fruit and may cause fruit to drop

Fact sheet

Fijian fruit fly

Fijian fruit fly

Bactrocera passiflorae. Photo by S Wilson, Secretariat of the Pacific Community

 

 
  • The Fijian fruit fly is a 6-8mm long, black-coloured fruit fly
  • Causes damage to a range of fruit including papaya
  • Currently in Fiji, Tonga, Tuvalu and Western Samoa
  • Could potentially be introduced by the importation of fruit containing fly larvae
  • Once in Australia it would be capable of causing significant damage to tropical and subtropical fruit production areas

Fact sheet

Papaya fly

Papaya fly

Toxotrypana curvicauda. Photo b Jeffrey W Lotz, Florida Department of Agriculture and Consumer Services, Bugwood.org

 

 
  • The papaya fly is a yellow-brown-coloured fly that is approximately 8-12.5 mm long with a 11-13.5 mm long ovipositor that attacks papaya fruit
  • Losses of up to 30% have been reported from Florida
  • The papaya fly is found in tropical and subtropical areas of the Americas from the southern USA to Venezuela
  • Could potentially enter Australia as larvae in infected fruit
  • If introduced it would severely affect the Australian papaya industry

Fact sheet

Philippine fruit fly

Philippine fruit fly

Bactrocera philippinensis. Photo by Anthony O’Toole, Secretariat of the Pacific Community

 

 
  • Larvae attack a wide range of hosts including papaya
  • Occurs in the Philippines and Palau
  • Methyl eugenol traps can be used to attract male fruit fly which will help to detect the pest
  • The fly can enter Australia as larva in infected fruit
  • If it enters Australia it is likely to have a significant impact on the papaya industry

Fact sheet

Melon fruit fly

Melon fruit fly

Bactrocera cucurbitae. Photo by Florida Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org

 

 
  • The melon fruit fly is a 6-8mm long small orange-brown coloured fly with distinctive brown spots on its wings
  • It affects a number of crops including melons, citrus and papaya
  • The fly could enter Australia as larva in infected fruit
  • Currently occurs in northern Africa, southern Asia, southeast Asia and Hawaii
  • Has the potential to affect Australia’s fruit producers, including papaya growers

Fact sheet

Exotic spider mites

 
  • Papaya is affected by a number of endemic (eg Two spotted spider mite T urticae) and exotic spider mites (eg T piercei and T truncates which both occur in Asia)
  • Spider mites feed on the plant’s sap causing leaves to become covered with spots of lighter green. Spider mites also produce silk webs on the undersides of leaves
    Together these symptoms are diagnostic of spider mites
  • Feeding also causes reduced fruit quality and yield
  • All spider mites are very small (usually only 0.5 mm long). The colour of adults can assist in identification – Adult T urticae are a yellow-green or red colour with two dark spots, while adult T piercei and T truncatus are usually a dark red colour without spots

Fact sheet

Bacterial crown rot

Bacterial crown rot

Erwinia papayae. Photo by L Vawdrey and R Fullerton

 

 
  • The bacteria cause the leaves of the papaya plant to yellow and die
  • Stems and crown often develop discoloured, water-soaked areas
  • Fruit can also be infected and become water-soaked and unsaleable
  • Disease is responsible for significant losses overseas and occurs in Malaysia, the Caribbean and the Mariana islands
  • Could be introduced on plant material or by visitors who have come into contact with infected plants

Fact sheet

Papaya pests already present in Australia

If pests or plant symptoms are found that are not normally present on your property, they may be new not only to your property, but to the region, or even Australia. Knowing how to recognise their presence and promptly report new pests is essential for containment and eradication programs.

Endemic fruit flies

Queensland fruit fly

Qfly. Photo by GT O’Loughlin, Department of Agriculture, Bugwood.org

  The Queensland fruit fly (Qfly) (Bactrocera tryoni) and Mediterranean fruit fly (Med fly) (Ceratitis capitata) are significant threats to papaya production and accessing vital export markets. Qfly is widespread throughout Queensland and has a limited distribution through south-eastern Australia. Medfly is restricted to Western Australia. Further information can be found at www.preventfruitfly.com.au

Papaya ringspot virus

Papaya ring spot

Potyvirus, Strain P. Photo by Dr Jose R Liberato DPI&F, PaDIL

 

 
  • Disease is caused by a virus that is spread by various aphids or by planting diseased plants
  • Virus causes yellow patterns to develop on leaves and leaf rolling to occur
  • Green ring-shaped markings develop on the skin of infected fruit and oily streaks develop on the plant’s stem. Trees may also become stunted if infected when young
  • Some mites may also cause leaf yellowing but obvious rings on fruit are tell-tale signs of the virus
  • Infection causes reduced fruit set and reduced vigour as well as reducing fruit quality and taste
  • There is no cure for this disease
  • Virus affects papaya, watermelon, pumpkins and cucurbits
  • Occurs in most tropical and subtropical countries including Australia
  • In Australia the virus is restricted to south east Queensland
  • A quarantine area exists in the south eastern corner of Queensland extending from the border north to Lowmead (24º30’ S) and from the coast west to near Theodore (150º E). Quarantine area details