A tri-trophic system was developed to rear classical biological control agents (Tamarixia radiata (Waterston) [Hymenoptera: Eulophidae] and Diaphorencyrtus aligarhensis (Shafee, Alam and Agaral) [Hymenoptera: Encyrtidae]) to be used against Diaphorina citri Kuwayama, a vector of the causative agent of citrus greening disease, Liberobacter asiaticum (L.). Psyllids were reared on orange jasmine, Murraya paniculata (L.) Jack, because it is considered a non-host of the greening pathogen. Psyllids and parasitoids were reared in small (ca. 2 m x 3 m) quarantine rooms. Several key limiting factors (abiotic and biotic) were identified in the system: plant (root) vigor and health; psyllid density on shoots; host: parasitoid ratio; and humidity and air flow in rearing cages. Collection and handling techniques were modified to capitalize on the behavior and biology of the psyllids and parasitoids, which reduced labor and handling time. Plants were re-used up to four times in quarantine to conserve the material, space, time, and labor to grow them and the labor and energy to dispose of them (autoclave). A host/female parasitoid ratio of approximately 100:1 resulted in the greatest yield of progeny, with up to 90% of hosts destroyed. Surviving psyllids were used to produce the next generation of psyllid nymphs. On average, 12 one-gallon potted plants generated 3,000 psyllid nymphs, which produced 200 adult psyllids and 844 T. radiata or 408 D. aligarhensis. The sex ratio of T. radiata was 1.8 female: 1 male (n=400), in the Taiwanese population and 2.0 female: 1 male (n=400), in the Vietnamese population. Only females were observed in this population of D. aligarhensis. Both parasitoids could be stored for up to 30 days at 75% RH and 17°C prior to field release.
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA