Title of article :
به آفت كش ها در شمال غرب ايرانOrnithodoros tholozani (Acari: Argasidae)سطح حساسيت
قوامي، محمد باقر نويسنده Department of Medical Entomology and Vector Control Ghavami, Mohammad Bagher , گلي، شريف نويسنده Department of Medical Entomology and Vector Control Goli, Sharif , محمدي، جمشيد نويسنده Department of Medical Entomology and Vector Control Mohammadi, Jamshid , وطن دوست، حسن نويسنده Department of Medical Entomology and Vector Control Vatandoost, Hassan
Issue Information :
فصلنامه با شماره پیاپی 0 سال 2015
The cave tick, Ornithodoros tholozani is the most important soft tick in central Asia
and the Middle East. The populations of this species live in human buildings and animal
shelters and are responsible for transmission of relapsing fever in different areas.
Residual spraying of pesticides is a common control measure against this species, and
vast regions of north west of Iran are sprayed annually with pyrethroids by the local
residents. Application of limited range of acaricides and similarity in their mode of
actions might contribute to emergenence of resistance, and decline of their efficacy.
Thus, this research was conducted to identify the susceptibility level of different
populations of this tick to some pesticides in old, well-known foci of relapsing fever.
Populations of this tick were collected from animal shelters of Mahneshan,
Khodabandeh, Tekab and Bijar districts in north west of Iran during 2012–2013. Adult
ticks were exposed to different doses of permethrin, lambdacyhalothrin and carbaryl
through topical and residual methods and mortality rate was measured after 24 hours.
The bioassay revealed different levels of tolerance to permethrin in various populations
of O. tholozani in the study area. The Bijar strain was susceptible and the LD50 and LC50
values for permethrin were 48.38 ng/tick and 96.98 µg/cm2 respectively. Tekab,
Khodabandeh and Mahneshan populations were resistant and resistance value in this
group was 2. The Bijar strain was also susceptible to lambdacyhalothrin and LD50 value
for this compound was 8.37 ng/tick. In spite of the susceptibility to pyrethroids in Bijar
strain, there was high resistance level to carbaryl and the LD50 value was 5.45 mg/tick.
Since different levels of resistance to permethrin were observed in various populations
of O. tholozani, reviewing and refining the control measures against ticks, applying new
formulations of acaricide mixtures and monitoring the susceptibility level of acaricides
seem necessary in these regions. Moreover, future studies to identify the molecular
characteristics of resistance to acaricides and determining the effective acaricide are
highly recommended in these areas.
Journal title :
Persian Journal of Acarology