The present study compares the in vitro efficacy of four chemical acaricides, viz. amitraz, coumaphos, deltamethrin and lindane, against Rhipicephalus (Boophilus) annulatus and Haemaphysalis bispinosa ticks based on adult immersion tests. Amitraz, at 350 ppm, elicited 29.2 ± 4.17% mortality against R. (B.) annulatus, 100% inhibition of fecundity and absence of hatching of eggs laid by treated ticks. The same compound at 300 ppm caused 62.5 ± 12.5% mortality against H. bispinosa, 96.7% inhibition of fecundity and complete blocking of eclosion. The LC value of amitraz against susceptible H. bispinosa was 181 ppm. Deltamethrin at 400 ppm, elicited 25.0 ± 4.81% adult R. (B.) annulatus mortality, 97.5% inhibition of fecundity and absence of egg hatching. Complete blocking of egg hatching was observed even at 30 ppm. However, deltamethrin (at 50 ppm) elicited 75.0 ± 10.76% mortality against H. bispinosa, 65.8% inhibition of fecundity and very low egg hatching (10%). The LC for deltamethrin against susceptible H. bispinosa was 33.8 ppm. Coumaphos at 50 ppm, caused mortality of 70.8 ± 4.17% with R. (B.) annulatus whereas 100% mortality was observed against H. bispinosa. The LC values of coumaphos against R. (B.) annulatus and H. bispinosa were 9 and 8.75 ppm, respectively. Complete inhibition (100%) of fecundity was observed even at 30 ppm against both parasites. Complete blocking of egg hatching was also observed even at 10 ppm of coumaphos. Lindane at 1000 ppm caused mortality of 87.5 ± 7.98% against R. (B.) annulatus and 83.3% mortality against H. bispinosa at 100 ppm. The LC values of lindane against R. (B.) annulatus and H. bispinosa were 157 and 8.61 ppm, respectively. Complete inhibition of fecundity was observed with R. (B.) annulatus treated with lindane above 200 ppm and with H. bispinosa at a concentration above 50 ppm. Complete blocking of egg hatching was observed in R. (B.) annulatus, even at 100 ppm. Lindane caused 100% blocking of egg hatching at 1 ppm in the case of H. bispinosa.

Since time immemorial, human beings have used various parts of plants in either prevention or treatment of ailments. Plants are rich sources of secondary metabolites such as alkaloids, steroids, terpenoids, flavonoids, and phenolic compounds with a high structural diversity. Many plants/herbs with specific biological activities such as antitumor, antioxidant, anti-inflammatory, antifungal, sedative, and acaricidal activity have been reported. Artemisia nilagirica (C. B. Clarke) Pamp. (Compositae) is a plant traditionally used for insect control in the southern part of India. Previous studies have demonstrated the activity of Artemisia species against pests. The present study thus evaluates the acaricidal activity of crude ethanolic extract of A. nilagirica leaves and its fractions against Rhipicephalus (Boophilus) annulatus. Ticks are ectoparasites that transmit several protozoal, viral, and rickettsial diseases. In south India, R. (B.) annulatus is the commonly observed tick species. Control of these acarine parasites that adversely affect milk and meat production is a tough task. Chemical acaricides such as organophosphates, synthetic pyrethroids, amitraz, and ivermectin are commonly used in tick control. The high cost, environmental hazards, and development of acaricidal resistance are some of the drawbacks of these chemical acaricides. Plant-based formulations are one of the promising approaches for the control of ectoparasites. Previously, extracts from various medicinal/aromatic plants were reported for acaricidal activity from our laboratory, such as Tetrastigma leucostaphylum (Dennst.) Alston, Chassalia curviflora (Wall.) Thwaites, Jatropha curcas L., and Ageratum conyzoides Hieron. Biochemical quantification, fluorescence analysis, and primary phytochemical analysis are already reported for the ethanolic extract and its fractions of areal parts of A. nilagirica. Phytochemical characterization of ethanolic extract of A. nilagirica from Kerala, India was shown to have the presence of terpenoids, flavonoids, steroids, saponins, fixed oils and fats, tannins, and glycosides.

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Plants constitute a rich source of bioactive compounds and its acaricidal effect is increasingly been investigated as a potential solution against acaricide resistance. In the present study, the in vitro efficacy of crude ethanolic extract of leaves of Sphaeranthus indicus, its fractions (hexane, chloroform, butanol and water) and subfractions of the active acaricidal fraction were evaluated against Rhipicephalus (Boophilus) annulatus using the adult immersion technique (AIT). The percentage of adult mortality, inhibition of fecundity and hatching rate were assessed. The crude ethanolic extract of leaves of Sphaeranthus indicus revealed hundred per cent adult mortality and inhibition of fecundity at a concentration of 250 mg/mL. Among the four fractions of this extract tested, hexane fraction showed concentration dependent delayed adult tick mortality. At 10 per cent concentration of hexane fraction, 87.41 per cent mortality and 77.78 per cent inhibition of fecundity were observed. Among the 14 subfractions of the active hexane fraction, the subfraction 4 (at 2000 ppm) produced 45.83 per cent mortality and 41.06 per cent inhibition of fecundity. It may be concluded that the hexane fraction of the leaves of ethanolic extract of S. indicus and its subfraction 4 revealed significant acaricidal effects.

Introduction:The anthelmintic activity of various extracts of leaves of Ocimum sanctum and Mallotus phillipensis was assessed in vitro against Setaria digitata. Materials and Methods: The leaves of Ocimum sanctum and Mallotus phillipensis were collected and were extracted using methanol, dried and stored under refrigeration till further use. The aqueous extract was taken as a decoction. The methanolic extract was further fractionated by taking solvents of increasing polarity viz, hexane, chloroform, n-butanol and water. The extract as well as the fractions were analysed qualitatively for various phytochemical constituents. Fresh nematodes (Setaria digitata) were recovered manually from the peritoneum of infested buffalo, were washed and transferred to the extract containing petriplates (concentrations of 50, 25, 12.5, 6.25, 3.125 and 1.56 mg/ml) immediately and the motility/death of Setaria digitata was noted. Results: The presence of flavonoids and tannins were detected in all the extracts where was phenolics as absent in the hexane fraction. The methanolic extract of Tulsi and Kamla produced death of nematodes in concentrations of 3.125 mg/ml and the extract of tulsi was found to be more potent. Similar results were also observed in the case of hydro alcoholic extract whereas the aqueous extract showed no effect. The chloroform fraction of Ocimum sanctum and n-butanol and chloroform fractions of Mallotus were equally potent in inhibiting the motility and producing death of the worms. The control drug, albendazole produced death in 30 minutes in both the concentrations. Conclusion: It could be concluded that higher doses of the extract are as potent as albendazole.Key words: Anthelmintic, Albendazole, Mallotus phillipensis, Ociumum sanctum, Setaria digitata. SUMMARY• The phytochemical analysis revealed the presence of tannins, flavonoids, terpenes and phenolic compounds in almost all extracts of Ocimum sanctum and Mallotus phillipensis.• Methanolic and hydroalcoholic extracts of Mallotus phillipensis produced death of Setaria in concentrations of 1.56 mg/ml where as Tulsi extracts did it at 3.125 mg/ml.• The extracts showed no toxicity on acute oral toxicity testing in rats.• Presence of saponins and tannins may be the cause of the anthelmintic property of the extracts.