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In the present study, the crude aqueous and chloroform extracts of Annona squamosa was tested for its in-vitro acaricidal efficacy against Rhipicephalus microplus ticks. Concentrations of 2.5%, 5%, 7.5%, 10% and 12.5% were tested against adult ticks whereas 0.312%, 0.625%, 1.25% and 2.5% were tested against larvae. No significant mortality and effect on oviposition was observed using aqueous extract, however, chloroform extract showed strong activity against both viz. adults and larvae. The highest adult mortality was observed at 12.5% concentration and determined LC50 and LC90 values were 5.24% and 14.12% respectively. A dose dependent reduction in egg laying capacity of treated female was observed in all concentrations compared to control group. The recorded mean mortality of larvae was 13.45 ± 0.73, 71.04 ± 1.10, 98.28 ± 0.39 and 100 ± 0.00 observed at 0, 0.312%, 0.625%, 1.25% and 2.5% of concentrations respectively. [ABSTRACT FROM AUTHOR]

The aqueous and chloroform extracts obtained from leaves of Adhatoda vasica were evaluated for acaricidal activity against engorged females of Rhipicephalus microplus and their larvae. No significant mortality of adult ticks was observed in the tested concentration of aqueous extract except at 80%. Whereas, chloroform extract showed a dosedependent increase in adult mortality, and LC50 and LC90 values were determined as 10.47% and 11.74%, respectively. A significant difference in egg hatching of laid eggs was observed at all concentrations tested and 98.55% inhibition of hatching was observed at 12.5% concentration. Dose-dependent larval mortality was observed in larval immersion test with various concentrations of chloroform extract with LC 50 and LC 90 values of 0.51%, and 1.09%, respectively. The results indicate that the chloroform extract of Adhatoda vasica could have very good in vitro acaricidal activities on adult and larval stages of Rhipicephalus microplus ticks. [ABSTRACT FROM AUTHOR]