T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Wasp (Tomato/potato psyllid wasp) Tamarixia triozae

Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Suborder: Apocrita
Superfamily: Chalcidoidea
Family: Eulophidae
Genus: Tamarixia
Species: T. triozae
Binominal name: Tamarixia triozae
Common name: Tomato/potato psyllid wasp

Tamarixia triozae is a small, black, winged red-eyed, is a parasitoid wasp that is found mainly in North America and Mexico. Its one host is Bactericera cockerelli which is a psyllid which has a long history of causing major crop losses in Mexico, USA and Canada. Tamarixia triozae lays its eggs on the surface of psyllid nymphs (the host). Once hatched, the eggs develop into larvae that feed on the psyllid nymphs, eventually killing them.

Bactericera cockerelli is a psyllid native to southern North America. They are commonly found on potato and tomato crops hence the common names tomato/potato psyllid. There has be up to 20 genera recorded as hosts including capsicum and tamarillo. Tomato potato psyllid was first recorded in New Zealand in May/June 2006 from greenhouses growing tomatoes near Auckland and since then has spread throughout solanaceous crop growing areas in the North and South Islands of New Zealand and is now considered a major economic pest. The psyllid can also transmit a bacterial pathogen, Candidatus Liberibacter solanacearum, that causes 'Zebra Chip', a characteristic discolouring of the tuber flesh in affected plants.
Bactericera cockerelli psyllids has three life stages – egg, nymph and adult. Adult females lay eggs on the upper and lower surface of host plant leaves. Both nymphs and adults feed on the underside of leaves in the phloem (living tissue that carries organic nutrients). This causes discoloration (called psyllid yellows) and stunting of the plant, with poor or little fruit growth probably the result of a toxin. The immature nymphs are very small, inconspicuous, scale like and are mostly sedentary.

On 17 June 2016 New Zealand’s Environmental Protection Authority (EPA) approved the release of Tamarixia triozae as a biological control agent to combat a psyllid (plant louse) Bactericera cockerelli.