A field test on the effectiveness of male annihilation technique against Bactrocera dorsalis (Diptera: Tephritidae) at varying application densities

Authors: Manoukis, Nicholas; Vargas, Roger; Carvalho, Lori; FEZZA, THOMAS - Animal And Plant Health Inspection Service (APHIS); Wilson, Shannon; Collier, Travis; SHELLY, TODD - Animal And Plant Health Inspection Service (APHIS)

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/28/2019
Publication Date: 3/8/2019
Citation: Manoukis, N., Vargas, R.I., Carvalho, L.A., Fezza, T., Wilson, S.M., Collier, T.C., Shelly, T.E. 2019. A field test on the effectiveness of male annihilation technique against Bactrocera dorsalis (Diptera: Tephritidae) at varying application densities. PLoS One. 4(3):e0213337. https://doi.org/10.1371/journal.pone.0213337.
DOI: https://doi.org/10.1371/journal.pone.0213337

Interpretive Summary: This paper describes the results of experiments compare three numbers of lure/insecticide spots per unit area (densities) for killing invading fruit flies. Results indicate that the number of spots could be reduced with similar or improved killing ability from the standard now used against Oriental fruit fly. This means lower material, labor, and time costs, with higher effectiveness might be possible for programs targeting this economically damaging invasive pest of hundreds of fruit commodities.

Technical Abstract: Male Annihilation Technique (MAT) is a key tool to suppress or eradicate pestiferous tephritid fruit flies for which there exist powerful male lures. In the case of Bactrocera dorsalis (Hendel), a highly invasive and destructive species, current implementations of MAT utilize a combination of methyl eugenol (ME) and a toxicant such as spinosad (“SPLAT-MAT-ME”) applied at a high density in the treated area with the goal of attracting and killing an extremely high proportion of males. We conducted direct comparisons of trap captures of marked B.dorsalis males released under three experimental SPLAT-MAT-ME site densities (110, 220, and 440 per km2) near Hilo, Hawaii using both fresh and aged traps to evaluate the effectiveness of varying densities and how weathering of the SPLAT-MAT-ME formulation influenced any density effects observed. We measured decreasing effectiveness (percent kill) with increasing application density. We also estimated slightly higher average kill for any given density for weathered grids compared with fresh. Spatial analysis of the recapture patterns show similar relative patterns between densities. This study suggests that benefits for control and eradication programs would result from reducing the application density of MAT against B.dorsalis through reduced material use, labor costs, and higher effectiveness. Additional research in areas where MAT programs are currently undertaken would be helpful to corroborate this study’s findings.