The Perth metropolitan area has been declared an agricultural quarantine zone to prevent a destructive plant pest from spreading.
The tomato potato psyllid was recently found for the first time in Australia in nine Perth backyard vegetable crops and a commercial property north of the city.
The quarantine area includes Wanneroo in the north, Serpentine-Jarrahdale in the south and Mundaring in the east.
Until the end of June, commercial producers can't move host plants or any machinery, equipment, soil or gardening items used with a host plant out of the quarantine area.
Shaun Lindhe from Ausveg said the pest was first detected in New Zealand a decade ago, and it had cost an estimated $60 million each year for growers to manage it.
The psyllid attacks plants including potato, tomato, pepper, paprika, capsicum, chilli, eggplant, tamarillo, nightshade, matrimony vine, field bindweed and sweet potato.
Department of Argriculture and Food WA acting chief plant protection officer Sonya Broughton said adult psyllids resembled small winged aphids and were about 3mm long.
"The body is brownish and has white or yellowish markings on the thorax and a broad white band on the abdomen. Its wings are transparent and held vertically over the body," Dr Broughton said.
"Symptoms of damage on plants can include stunting, yellowing and purpling of leaves, distorted leaf growth and stem death."