DETECTION OF ORGANOPHOSPHATE (MALATHION) RESISTANCE STATUS IN HYALOMMA ANATOLICUM POPULATION FROM SRI MUKTSAR SAHIB DISTRICT OF PUNJAB

Resistance status against organophosphate (malathion) in Hyalomma anatolicum collected from Sri Muktsar Sahib, Punjab was estimated by adult immersion test. The engorged female ticks were immersed in progressively increasing concentrations of malathion for 2 min and mortality was recorded up to 14 days post treatment. The LC50 (95% confidence interval [CI]) and LC95 (95% CI) values were determined as 12364.74 (11230.5-13615.1) and 72379.62 (59376.2-88230.7) ppm, respectively with resistance factor (RF) of 28.95 (Level III resistance). The effect of malathion on reproductive parameters of treated adult female ticks viz. egg mass weight (EMW), reproductive index (RI) and percentage inhibition of oviposition (%IO) were also studied. The slope of mean EMW (95% CI) was -111.1 ± 18.79 (-170.9 to -51.30) and negative as with the increasing concentrations of malathion the survived ticks laid significantly (p= 0.0097) fewer eggs. The mean RI of treated ticks showed a decreasing trend and there was a significant increase (p= 0.0064) in the mean %IO in treated ticks with increasing drug concentrations.