Fıeld evaluation of the IGRs, Diflubenzuron, s-methprene, and bactierally-deprived insecticide, spinosad, against Culex pipiens molestus and Aedes albopictus mosquitoes in North-eastern Italy
Dalla Pozza G.1, Avella L. 2,Ceretti G.1 , Baldazzi L.3, Tagliapietra P.1, Ali A.4.
1 Department of Public Health, Azienda ULSS 12 Veneziana, P.le S.L. Giustiniani, 11/D. 30174 Venice, Italy.
2 R&D Department Chemtura Italy Srl, Latina, Italy
3 Via De Carolis, 27. 47900 Rimini, Italy.
4 Mid-Florida Research and Education Center and Department of Entomology and Nematology, University of Florida, 2725
Binion Road, Apopka, Florida 32703, USA
Initially effectiveness and residual activity of three insect growth regulator (IGR) commercial products, Device® SC 15 (15% AI diflubenzuron, flowable), Altosid® SR-10 (5% AI s-methoprene,
microencapsulated), and Proxilar® (4% AI pyriproxyfen, emulsifiable concentrate), and a bacterially-derived insecticide, Laser® (48% AI spinosad, emulsifiable concentrate), were evaluated
against mixed populations of Culex pipiens molestus and Aedes albopictus inhabiting manholes in north-eastern Italy. The test products were applied at recommended field-use rates (label) to the
manholes in Venice-Mestre (Venezia Province) and Riccione (Rimini Province). The post-treatment efficacy of the IGRs and spinosad was judged by monitoring inhibition of adult mosquito emergence (IE) weekly up to 11 weeks post-treatment, compared to the corresponding untreated manholes serving as controls in each study area. Device® SC 15 at 0.75 ppm AI, induced >90% IE of Cx. p. molestus for 8 and 7 weeks post-treatment at Venice-Mestre and Riccione, respectively, while simultaneously yielding similar (>90% IE) control of Ae. albopictus for 9 weeks (Venice-Mestre) and 7 weeks (Riccione) post-treatment. Altosid® SR-10 at 0.75 ppm AI resulted in good control (>90% IE) of both mosquito species for 4-5 weeks post-treatment in the two study areas.
Proxilar® applied at 0.2 ppm caused >90% IE of Cx. p. molestus for 5 weeks (Venice-Mestre) and 4 weeks (Riccione) post-treatment; this IGR gave >90% IE control of Ae. albopictus for 3 and 4 weeks post-treatment at Venice-Mestre and Riccione, respectively. Laser® at 1 ppm AI induced >90% IE of Cx. p. molestus for 8 weeks post-treatment at Venice-Mestre, and for 7 weeks at Riccione,
whereas Ae. albopictus emergence was reduced >90% IE for 6 weeks and 7 weeks posttreatment at the former and latter study area, respectively. Two-way ANOVA and Tuckey test revealed
significantly (P < 0.001) longer post-treatment persistence of Device® SC 15 and Laser® over Altosid® SR-10 and Proxilar® at the treatment rates employed in this study, providing superior
control of the two mosquito species in terms of magnitude and post-treatment time duration.