Tomato potato psyllid
Tomato potato psyllid (Bactericera cockerelli) is a tiny sap-sucking, winged insect.
It can spread a serious plant disease known as zebra chip in potato, caused by the Candidatus Liberibacter solanacearum (CLso) bacterium.
Background
The tomato potato psyllid (TPP) origin is unknown. It was first detected in Western Australia in February 2017 and there have been no confirmed reports in South Australia. TPP can spread:
- through movement of infested plants and plant materials, including fruit, vegetables and nursery stock
- on horticultural machinery and equipment
- by wind and flight – adult psyllids can fly short distances.
The Department of Primary Industries and Regional Development (WA) is working with the Western Australian horticulture industry to undertake surveillance and respond to the detection of TPP. A quarantine area is in effect for parts of WA to help minimise the spread.
The bacterium CLso has not been detected in Australia. Zebra chip requires TPP as a vector for movement between plants.
Importing restrictions
Condition 17 of the Plant Quarantine Standard (PQS), details restrictions and prohibitions on hosts in the solanaceae and convolvulaceae families. This affects products like potatoes, tomatoes, capsicums, eggplants and sweet potato.
Learn more about importing commercial plants and plant products into SA.
Biosecurity SA continues to undertake surveillance activities on commercial and residential properties across the state. This is essential to protect the state’s horticultural industry and prevent quarantine restrictions to trade.
Impacts
TPP causes significant production losses by feeding on tomato, potato, capsicum, chilli, goji berry, tamarillo, eggplant, sweet potato, and solanaceous weeds like nightshade.
The disease presents through symptoms such as:
- severe wilting of plants caused by high numbers of psyllids feeding
- yellowing or purpling leaf margins
- upward curling or cupping of leaves, dwarfing and stunting
- white sugar-like granules excreted by adults and nymphs, which coat the plant leaves and stems – this may lead to sooty mould or attract ants
- stem death, similar to other potato and tomato disorders.
Management
Management
Control TPP using biosecurity practices to limit spread between growing facilities. This includes:
- inspecting your crops regularly and reporting unusual growth
- using pest-free propagation material and seedlings, sourced from a reputable supplier
- keeping equipment and vehicles clean and free of plant matter
- wearing clean clothing before visiting other growers’ properties
- teaching on-farm hygiene practices to all workers and visitors.
Identification
When present in a crop, TPP can be seen jumping from the foliage when disturbed. They have 3 stages of development.
Eggs are up to 1mm long and attached to the plant by a short vertical thread. They are laid on the lower surface of leaves, or along the leaf stalk. Eggs are white at first, before turning yellow to orange after a few hours.
Nymphs are up to 2mm long, oval shaped, flattened and scale-like in appearance. Young nymphs are yellow with a pair of red eyes and 3 pairs of short legs. Older nymphs are greenish, fringed with hairs, and have visible wing buds.
Adult psyllids resemble small, winged cicadas and are about 3mm long. The body is brownish and has white or yellowish markings on the chest and a broad white band on the abdomen. Wings are transparent and held vertically over the body.