International Centre of Insect Physiology and Ecology (icipe), Nairobi 30772 - 00100, Kenya; Department of Biochemistry and Molecular Biology, Egerton University, Njoro 536 - 20115, Kenya.
International Centre of Insect Physiology and Ecology (icipe), Nairobi 30772 - 00100, Kenya.
Vet Parasitol. 2024 Jul;329:110210. doi: 10.1016/j.vetpar.2024.110210. Epub 2024 May 17.
The growing challenge of acaricide resistance and geographical range expansion of invasive tick species demands other interventions, like plant-based alternatives, for sustainable tick control. Leaves, flowers, seedpods, and twig branch extracts of Senna didymobotrya were analyzed using coupled gas chromatography mass spectrometry (GC-MS). Response of adult Amblyomma variegatum and Rhipicephalus appendiculatus to extracts was evaluated. The most attractive plant extract was fractionated and ticks' responses to its fractions assessed. Potential tick attractants in the attractive plant part extract and its fractions were identified by GC-MS analysis. Non- significant qualitative and quantitative differences were observed in the plant parts' extract composition (R = 0.6178). Flower extracts attracted both species, with a 0.1-fold higher attraction in A. variegatum compared to the standard attraction aggregation attachment pheromone (AAAP). Leaf and seedpod extracts repelled ticks at various concentrations. Bioassays after fractionating flower extracts identified hexane and ethyl acetate fractions as most attractive to A. variegatum (P < 0.001) and R. appendiculatus (P < 0.001), respectively. Chemical analysis of the most attractive extracts and fractions identified compounds, including documented acarine attractants, squalene and linoleic acid. A squalene and linoleic acid blend (1:1) at 1 mg/mL significantly attracted adult A. variegatum (P < 0.01) and R. appendiculatus (P < 0.001). The results of this study broaden comprehension of how ticks respond to plants in nature, and showcase the promising potential for integrating these insights into effective tick management programs.
杀蜱剂耐药性的日益严重以及入侵蜱种地理范围的扩大，要求采取其他干预措施，例如植物替代物，以实现可持续的蜱控制。使用气相色谱-质谱联用仪（GC-MS）对双荚决明的叶、花、豆荚和小枝提取物进行了分析。评估了成年钝缘蜱和边缘革蜱对提取物的反应。对最有吸引力的植物提取物进行了分段，并评估了其各部分对蜱的反应。通过 GC-MS 分析确定了有吸引力的植物部分提取物及其各部分中潜在的蜱引诱剂。植物部分提取物的组成在定性和定量上都没有明显差异（R = 0.6178）。花提取物吸引了两种蜱，与标准吸引聚集附着信息素（AAAP）相比，A. variegatum 的吸引力高出 0.1 倍。叶片和豆荚提取物在不同浓度下均排斥蜱。对花提取物进行分段后的生物测定确定了正己烷和乙酸乙酯为最吸引 A. variegatum（P < 0.001）和 R. appendiculatus（P < 0.001）的部分。对最有吸引力的提取物和部分进行化学分析，确定了包括有记录的螨虫引诱剂角鲨烯和亚油酸在内的化合物。角鲨烯和亚油酸（1:1）混合物以 1mg/mL 的浓度显著吸引成年 A. variegatum（P < 0.01）和 R. appendiculatus（P < 0.001）。本研究的结果拓宽了对蜱在自然界中如何对植物产生反应的理解，并展示了将这些见解纳入有效的蜱管理计划的有希望的潜力。
