Jawwad A. Qureshi and Philip A. Stansly Southwest Florida Research and Education Center Field release and evaluation of Tamarixia radiata parasitism against Asian citrus psyllid

Adult Parasitoid: Tamarixia radiata (Hymenoptera: Eulophidae) Larva Prepupa Egg Mummies M. Rogers A. Urebaneja

Our efforts to enhance parasitism rates of T. radiata in the United States  Statewide evaluation of T. radiata parasitism from previously released and established parasitoids imported from Taiwan and south Vietnam by Hoy and Nguyen ( ) (Qureshi et al. 2009)  Import and introduction of T. radiata from Pakistan, South China, and North Vietnam, and their genetic characterization (Barr et al. 2010)  Mass production and release of previously established and new parasitoids  Collaboration with Orange Co. and DPI to establish large scale mass rearing facilities  Evaluation of parasitism rates of newly released parasitoids

Previous and recent releases of T. radiata in Florida  1999 – 2001: 37, 000 from colonies established at DPI Gainesville, FL, from parasitoids imported from Taiwan and south Vietnam (Hoy and Nguyen 2001, Skelly and Hoy 2004)  2009 (Mar – Dec): 32, 000 from colony established at Southwest Florida Research and Education Center (SWFREC), Immokalee, FL, from previously imported and established parasitoids  (Oct – Jan): 36, 000 from colonies established at DPI Gainesville, FL, from parasitoids imported from Pakistan, South China, and North Vietnam

Methods to evaluate parasitism rates  Cages with apertures to allow parasitoids but not the large size predators to access the colonies in the field. (Michaud, 2004, Qureshi and Stansly, 2009)  Examination of nymphs under the microscope to look for parasitoid eggs larvae or pupae (Qureshi et al. 2009) Larva Egg Prepupa

Methods to evaluate parasitism rates  Exposure of plants infested with psyllid nymphs to natural populations of the parasitoid in the field (Qureshi and Stansly, 2009)  Laboratory rearing of field collected nymphs through adult emergence. (Qureshi and Stansly, 2009, Qureshi et al. 2009)

Incidence of parasitism by T. radiata on citrus in three regions of Florida 20% 39% 56% Qureshi et al. (2009)

Incidence of parasitism by T. radiata on citrus in experimental blocks at SWFREC Qureshi and Stansly (2009)

Incidence of parasitism by T. radiata on citrus in Isabela, Puerto Rico Pluke et. al. (2008)

Releases of T. radiata imported from Taiwan and South Vietnam

Releases of T. radiata imported from Pakistan, South China, and North Vietnam

Incidence of parasitism by T. radiata at SWFREC 2009

Highest parasitism observed during Oct – Nov in conventional groves with and without T. radiata releases, 2009 Groves with releases Groves without releases Average 10% 20% n = 28 n = 35 n = 49 n = 491 Parasitism (%)

Parasitism rates in groves with releases of newly imported T. radiata (October 2009) n = 1094 n = 21 n = 10 Pakistan S. China N. Vietnam

Nymphs parasitized by T. radiata on sentinel plants exposed for two to three weeks at SWFREC and a conventional grove, Immokalee, FL n = 50 n = 28 n = 296 n = 416 n = 188

Conclusions and Future Directions  Colonies of previously established and recently imported strains from Pakistan, South China, and North Vietnam are now well established  Mass production, release and evaluation in progress  Parasitism rates of 40-60% were observed when more nymphs were available in the groves or recovered on sentinel plants  Parasitism rates averaged 50% more in the groves where releases were made compared to groves with no releases  More T. radiata will be produced and released in 2010, particularly in spring flush  Impact of releases will be measured in both treated and untreated conventional and organic groves

Acknowledgements  Funding: Florida Citrus Production Research Advisory Council  All participating growers and collaborators from Pakistan, China, and Vietnam  Division of Plant Industry for quarantine facility and Ru Nguyen for rearing of imported strains  Animal Plant Health and Inspection Service for permit to release the newly imported strains  M. Triana, J. Mendez, S. Croxton, UF-IFAS Immokalee for technical assistance