Psyllids

Adult psyllids resemble tiny cicadas, typically only a few millimetres long, with clear or patterned wings held roof-like over the body and strong hind legs used for jumping when disturbed. Nymphs are flattened, scale-like, and often produce distinctive waxy filaments or tubules.

Signs of infestation include curled or distorted new growth, honeydew and associated sooty mould, and waxy nymphal secretions on the undersides of leaves.

Psyllids develop through incomplete metamorphosis, with flattened nymphs progressing through several stages before becoming winged adults. Most species have multiple generations per year and often colonise a narrow range of related host plants.

Adults can disperse between host plants through short flights assisted by wind, which is significant both for colonising new orchards or fields and for spreading pathogens some species vector.

Feeding can distort shoots and leaves and produce honeydew that supports sooty mould growth, but the transmission of bacterial pathogens associated with several serious citrus and solanaceous crop diseases is often the more damaging consequence of psyllid infestation.

Host crops include orange, lemon, pear, and tomato, reflecting the strong host associations of different psyllid species.

Yellow sticky traps, tap or beat sampling over a collection tray, and visual scouting of new growth for nymphs and honeydew are common methods used to track psyllid presence and inform management timing.

Psyllid management fits within integrated pest management, combining several tactics rather than relying on any single approach.

• Conserve parasitoid wasps, predatory bugs, and lacewings
• Use certified, pest-free planting material where available
• Remove or manage alternate host plants near susceptible crops
• Monitor with sticky traps and local thresholds to guide any intervention