ABSTRACT

Development of acaricidal resistance and environmental pollution has driven need for eco-friendly pesticides and herbal acaricides. Rhizome extracts of Curcuma longa in three different solvents (acetone, chloroform and ethanol) were used in the range of 0.625–10.0% for larval immersion test against unfed larvae of Rhipicephalus microplus ticks. HPLC-PDA chromatogram showed peak of Bis demethoxy curcumin, Demethoxy curcumin and Curcumin at 430 nm with the retention time of 14.502, 15.840 and 17.33 min, respectively, in a standard marker preparation and in the sample. Ethanolic extract showed much higher yield of Demethoxy curcumin and Curcumin in comparison to acetone and chloroform extracts. Mortality rates of larval ticks were in dose-dependent manner and 100% mortality of tick larvae was achieved at 10% concentration for acetone and chloroform extracts whereas ethanolic extract showed 100% mortality of tick larvae from 7.5% concentration onwards. Among the three extracts, the highest acaricidal activity was shown by ethanolic extract with 2.43%, 9.12%, 13.26% and 26.77% values of LC₅₀, LC₉₀, LC₉₅ and LC_99, respectively. Significant larvicidal activity of C. longa rhizome extracts against unfed larvae of R. microplus qualifies them as green pesticides which could be combined with other tools for integrated pest management.

摘要

杀螨剂抗性和环境污染的发展推动了对环保杀虫剂和草药杀螨剂的需求。的根茎提取物姜黄在三种不同的溶剂（丙酮，氯仿，乙醇等）中的0.625-10.0％针对的未喂食的幼虫幼虫浸渍试验的范围内，使用扇头蜱microplus蜱虫。HPLC-PDA 色谱图显示双脱甲氧基姜黄素、脱甲氧基姜黄素和姜黄素的峰在 430 nm 处，保留时间分别为 14.502、15.840 和 17.33 分钟，在标准标记制剂和样品中。与丙酮和氯仿提取物相比，乙醇提取物显示出更高的脱甲氧基姜黄素和姜黄素产量。蜱幼虫死亡率呈剂量依赖性，丙酮和氯仿提取物浓度为 10% 时蜱幼虫死亡率为 100%，而乙醇提取物从 7.5% 浓度开始显示蜱幼虫死亡率为 100%。在三种提取物中，乙醇提取物的杀螨活性最高，LC ₅₀、LC ₉₀、LC _{95 分别}为2.43%、9.12%、13.26%和26.77%和 LC _99，分别。C. longa根茎提取物对未饲喂的R. microplus幼虫的显着杀幼虫活性使它们成为绿色杀虫剂，可与其他害虫综合治理工具结合使用。