The Tomato potato psyllid is an exotic insect that attacks the Solanaceae family of plants which include potato, tomato, eggplant, capsicum, chilli and tamarillo. It also attacks sweet potato and others in the Convolvulaceae plant family.
In February 2017 the Tomato potato psyllid was detected in a range of commercial and backyard crops across the Perth metropolitan area. There have also been a small number of detections outside of the Perth metropolitan area including Gingin and parts of the South-West.
Since its detection, the Department of Agriculture and Food Western Australia (DAFWA) has been working to contain and suppress the psyllid, in addition to conducting intensive surveillance. Surveillance is occurring on commercial crops and backyard plants, and will also be conducted on solanaceous weeds that are known to be a host for the tomato potato psyllid.
DAFWA has put in place a Quarantine Area Notice for the Perth Metropolitan Area and surrounds to help prevent the spread of the tomato potato psyllid. There is more information about the restricted area, including a map, on the Department of Agriculture and Food website.
The National Management Group - comprising all Australian governments, affected industries and Plant Health Australia – agreed to a short-term national response plan for the incursion of TPP.
The response plan guides detection, suppression, and control efforts that are already underway.
The national Consultative Committee on Emergency Plant Pests (CCEPP) meets regularly to discuss the incursion. The committee provides technical advice on response activities that are being conducted by the DAFWA – which is the lead jurisdiction for this response.
Identifying and reporting affected plants
Everyone in Western Australia who grows potato, tomato, eggplant, capsicum, chilli, tamarillo, or sweet potato plants, needs to check their plants for signs of the tomato potato psyllid. It doesn’t matter whether you are a commercial grower or only keep a few plants in your backyard.
About tomato potato psyllid
Tomato potato psyllid can spread through the movement of tomato, capsicum, eggplant, tamarillo and other solanaceous plant material. It can also occur on other hosts including the Convolvulaceae plant family - which includes sweet potato. It can also disperse through natural pathways such as flight and on the wind.
The tomato potato psyllid is a significant production pest in other countries where it is present, which are USA, Central America, New Zealand and Norfolk Island which is an external Australian territory.
What to look for
The Tomato potato psyllid (Bactericera cockerelli)) is a tiny sap-sucking insect. Adults resemble small winged cicadas and are about 3mm long.
The body is brownish and has white or yellowish markings on the thorax and a broad white band on the abdomen. Wings are transparent and held vertically over the body.
Tomato potato psyllid on a leaf. Photo courtesy of Department of Agriculture and Food, Western Australia.
When present in a crop, the noticeable signs of the tomato potato psyllid include:
- Insects jumping from the foliage when disturbed. Adult psyllids are sometimes called jumping plant lice as they readily jump and fly when disturbed.
- Severe wilting of plants occurs when there are large numbers of psyllids feeding.
- Yellowing of leaf margins and upward curling of the leaves.
- White sugar-like granules that are excreted by adults and nymphs. These granules coat the plant leaves and stems, and can lead to the development of sooty mould.
- Honeydew and psyllid sugar make the plants sticky and they often appear dirty.
- Shortening of stem internodes occurs.
- The death of the stem is similar to other potato and tomato disorders.
About Candidatus Liberibacter solanacearum
The Tomato potato psyllid is a known vector (can carry) the bacterium (Candidatus Liberibacter solanacearum) which causes Zebra chip disease in potatoes. This bacterium is also exotic to Australia and poses a threat to important horticultural crops such as potatoes, capsicum, chilli, tomatoes, eggplant and tamarillo.
There has been no detection of CLso to date. A suspect case in a commercial horticulture property in Perth, in mid-March 2017, has been resolved following extensive testing on the property, with no confirmed positive detections.
Despite having no confirmed detections of CSlo to date, growers should always check their plants for signs of pests and disease.
What to look for
Zebra chip disease results in reduced crop yield and crop health, stem death, yellowing of leaf tissue, and misshapen tubers.
Symptoms of the Candidatus Liberibacter bacterium on potatoes, tomatoes, capsicum and chilli may look similar to other plant conditions, so growers are urged to be vigilant for the following symptoms:
- In tomatoes, plants may become stunted or abnormally elongated. Leaf curling and yellowing occurs on the foliage. The fruit develops unevenly. Tomatoes may be misshapen or no fruit is produced or there is an over-production of small, non-commercial grade fruit. Symptoms vary in severity between cultivars.
- In capsicums and chillies, parts of the plant may die back. In foliage, leaves become misshapen, pale green or yellow with spiky tips and leaf stalks appear stunted. Flowers may drop prematurely. Symptoms vary in severity between cultivars.
- Symptoms of zebra chip in potatoes include the plant having shortened internodes and aerial tubers may develop in the leaf nodes. Potato tops are likely to be smaller than normal. The foliage turns yellow and may have a burnt or purplish appearance.
Stems may die completely but regrowth from the base may occur. Tubers from affected plants may have small stalked tubers protruding from the main tuber, called ‘chaining’, and when cut may show internal browning of the vascular ring or brownish streaks along the medullary rays.
Neither the psyllid or the bacterium pose a risk to human health.
Report your detection
If you think the Tomato potato psyllid or the bacterium that causes Zebra chip disease may be present in your plants, you must report this to the Exotic Plant Pest Hotline on 1800 084 881. Alternatively, you can use the DAFWA MyPestGuide reporting app.
Detections outside of Western Australia can also be reported to the Exotic Plant Pest Hotline on 1800 084 881. This number will put you in contact with yourstate or territory department of agriculture or primary industries.