Using DNA markers and isotope marking to test the effectiveness of fluorescent dust marking during a sterile insect technique program targeting Bactrocera tryoni (Diptera: Tephritidae) in Australia

Dispersal of immature and sexually mature Queensland fruit fly, Bactrocera tryoni (Froggatt) from releases made at a single point was assessed from recapture rates obtained by using arrays of traps. The recapture data (pertaining to distances up to 480 m) fitted both logarithmic and Cauchy models although the fits for the releases of immature flies were inferior because of high variability in catches at certain distances. When combined with data previously published for longer distances, a Cauchy model fitted data for releases of immature flies well and indicated that the median distance dispersed after emerging from the puparium was ~120 m and that 90% of flies would displace less than 800 m despite the fact that a consistent trend in declining catch rates can be obtained up to at least 85 km. This is consistent with the tail of the Cauchy distribution having a slope congruent with a negative power curve and thus being scale invariant for longer distances. The distribution of recaptured flies that were released as adults also fitted a Cauchy model with a tail of the same slope, suggesting that the spatial distribution of long-distance dispersers is not only scale invariant but also age invariant. This has significance to the ability of surveillance trapping arrays to detect infestations and also to methods of distributing insects for the sterile insect technique. Whereas the spread of invading propagules in the first generation is likely to be limited by a decline to non-viable density within 1 km or less of the incursion point, the influence of larger infestations on nearby uninfested regions would be limited by the longevity of the dispersers.

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Desiccation resistance of wild and mass-reared Bactrocera tryoni (Diptera: Tephritidae)

Bulletin of Entomological Research ◽

10.1017/s0007485313000394 ◽

2013 ◽

Vol 103 (6) ◽

pp. 690-699 ◽

Cited By ~ 21

Author(s):

C.W. Weldon ◽

S. Yap ◽

P.W. Taylor

Keyword(s):

Water Stress ◽

Sterile Insect Technique ◽

Reproductive Development ◽

Desiccation Resistance ◽

Sharp Decline ◽

Bactrocera Tryoni ◽

Dehydration Tolerance ◽

Dry Conditions ◽

Access To Food ◽

Adult Mass

AbstractIn pest management programmes that incorporate the sterile insect technique (SIT), the ability of mass-reared insects to tolerate dry conditions may influence their survival after release in the field. In the present study, desiccation resistance of adult mass-reared Queensland fruit flies, Bactrocera tryoni (Frogatt) (Diptera: Tephritidae), that are routinely released in SIT programmes was compared with that of wild flies at 1, 10 and 20 days after adult eclosion. Under dry conditions without access to food or water, longevity of mass-reared B. tryoni was significantly less than that of their wild counterparts. Desiccation resistance of mass-reared flies declined monotonically with age, but this was not the case for wild flies. The sharp decline in desiccation resistance of mass-reared flies as they aged was likely explained by decreased dehydration tolerance. As in an earlier study, desiccation resistance of females was significantly lower than that of males but this was particularly pronounced in mass-reared females. Female susceptibility to dry conditions corresponded with declining dehydration tolerance with age and associated patterns of reproductive development, which suggests that water content of their oocyte load is not available for survival during periods of water stress.

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Residual toxicity of insecticides used in Tunisian citrus orchards on the imported parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae): Implications for IPM program of Ceratitis capitata (Diptera: Tephritidae)

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2017153-10734 ◽

2017 ◽

Vol 15 (3) ◽

pp. e1008 ◽

Cited By ~ 5

Author(s):

Ahlem Harbi ◽

Khaled Abbes ◽

Beatriz Sabater-Muñoz ◽

Francisco Beitia ◽

Brahim Chermiti

Keyword(s):

Side Effects ◽

Sterile Insect Technique ◽

Ceratitis Capitata ◽

Fruit Fly ◽

Pilot Scale ◽

Successful Implementation ◽

Residual Toxicity ◽

Diachasmimorpha Longicaudata ◽

Sterile Insect Technique Program ◽

Citrus Orchards

Citrus agro-industry is globally harshened mainly by Ceratitis capitata (Wiedemann), the most worldwide destructive tephritid fruit fly species. Citrus agro-industry is one of the pillars of Tunisia economy, and by hence, harshened by this species. Tunisia has established an Integrated Pest Management (IPM) programme against citrus pests, including C. capitata, that rely on the structured use of pesticides, on the application several trapping protocols, along with pilot-scale sterile insect technique program and, since 2013, with pilot-scale releases of the braconid parasitoid Diachasmimorpha longicaudata Ashmed (Hymenoptera: Braconidae). Insecticide side-effects on parasitoids and other natural enemies are being requested for a successful implementation of biological control within any IPM programme. However, these data are almost scarce for the braconid species D. longicaudata. To this end, we have determined the side-effects of malathion, methidathion, acetamiprid, azadiractin, abamectin, deltametrin+thiacloprid and spinosad, as the most popular insecticides used in Tunisia either as fresh residues or at several aged time points, on the parasitoid D. longicaudata according the IOBC pesticide harm-classification. IOBC classification evolution of residues over time had allowed determining the best combination of pesticide applications in a structured fashion with the viable releases of D. longicaudata for the control of C. capitata in Tunisian citrus agro-ecosystems.

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