Autosomal inheritance of deltamethrin resistance in field populations of Triatoma infestans (Heteroptera: Reduviidae) from Argentina.
BACKGROUND
Triatoma infestans (Klug) is the major Chagas disease vector in the Southern Cone area of South America, and its chemical control is based on the use of pyrethroid insecticides. Resistance to deltamethrin in Salta Province, Argentina, has been detected in field populations since 2002, causing the failure of vector control campaigns in this disease-endemic area. The inheritance of deltamethrin resistance in T. infestans was evaluated through reciprocal crosses conducted between resistant and susceptible insects.


RESULTS
The response of the reciprocally mated insects' progeny to deltamethrin was intermediate between the highly resistant and the susceptible parent colonies. Lack of significant differences between the LD(50) and resistance ratios of the reciprocally mated insects indicated no sex linkage on this trait.


CONCLUSIONS
Bioassay results, in addition to degree of dominance calculations, suggest that the resistance to deltamethrin in T. infestans is controlled by semi-dominant, autosomally inherited factors.
Germano
Mónica D
MD
Centro de Investigaciones de Plagas e Insecticidas (CIPEIN, CITEFA-CONICET), Villa Martelli, Provincia de Buenos Aires, Argentina. mgermano@citefa.gov.ar
Vassena
Claudia V
CV
Picollo
María I
MI
D000818:Animals; D001118:Argentina; D004351:Drug Resistance / Q000235:genetics*; D040582:Inheritance Patterns / Q000235:genetics*; D007306:Insecticides; D007753:Laboratories; D009570:Nitriles; D011722:Pyrethrins; D014224:Triatoma / Q000235:genetics*
D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin