INVESTIGADORES
PICOLLO Maria Ines
congresos y reuniones científicas
Título:
Is there any alternative insecticide to control pyrethroid-resistant Triatoma infestans (Hemiptera: Reduviidae) populations in the Gran Chaco Ecoregion?
Autor/es:
G. CARVAJAL; M. I. PICOLLO; A. TOLOZA
Lugar:
Austin
Reunión:
Congreso; ESA Annual Meetings; 2013
Institución organizadora:
Entomological Society of America
Resumen:
The prevention of Chagas Disease is
based on the chemical control of the vector using pyrethroid insecticides. In
the last decade, high resistance levels to these insecticides have been
detected. Actually, the only alternative insecticides to control pyrethroid
resistant populations are based in the use of organophosphate compound. We
analyze the toxicity of 7 non-pyrethorid insecticides against two T. infestans
populations, a susceptible (S) and a deltamethrin-resistant (R) population with
a resistant level (RL) of 1,031.
There was no significant variation
in the LD50s after 24, 48 and 72 h of initial topical application on both S
(LD50=5.2 ng/insect) and R (LD50= 9.2 ng/insect) populations. This could
indicate that the toxicological effect of the active ingredient remains stable
through the time.
The nutritional condition
(starvation/feeding) of the insects had no significant influence on the
insecticidal activity of the imidacloprid on either populations S (LD50starved
= 5.2 ng/I and LD50feeded = 3.9 ng/i) or R (LD50starved = 9.2 ng/I and
LD50feeded = 10.8 ng/i). Thus, the rate of penetration associated with
physicochemical modifications of cuticle after feeding seems not to alter the
relatively fast-acting effect after topical application.
The above results indicate that the
neonicotinoid imidacloprid seems to be a possible alternative to pyrethroid
insecticides in areas where T. infestans developed resistance. However, the
adequate formulation of the active ingredient is essential in their
effectiveness. Finally, the implementation of an
integrative control strategy is also discussed