Sankar Manu, Yadav Divya, Kumar Sarita
Department of Zoology, Acharya Narendra Dev College, University of Delhi, New Delhi, India.
Front Physiol. 2024 Dec 16;15:1476259. doi: 10.3389/fphys.2024.1476259. eCollection 2024.
, the vector of multiple arboviral diseases, is a prime health concern worldwide. The surge in borne diseases emphasizes the urgent need for efficient vector control measures. Synthetic pesticides used traditionally, however, present environmental concerns and issues like resistance development, causing the use of higher chemical doses. Hence, alternate interventions like the use of insect growth regulators (diflubenzuron; DFB) show promise because of their unique mechanism of action and environmental safety. Nevertheless, mosquitoes have the potential to develop resistance to any chemical. Thus, the present study investigates the use of DFB in combination with verapamil (DFB-V; 1:10) as a possible mosquito intervention measure.
The effects of both DFB and DFB-V were assessed on the larval development, adult emergence and expression of detoxification enzymes, non-specific esterases, glutathione S-transferase (GST), acetylcholinesterase (AChE), and monooxygenases in laboratory-reared (AND-) and wild-caught (GVD-) strains of . The effects on the survival of non-target organisms were also investigated.
The investigations showed that DFB-V treatment of the fourth instars caused a 1.16-1.37 fold higher adult emergence suppression than DFB alone, reducing the IE values. The DFB treatment increased β-esterases, AChE, and monooxygenases but reduced the GST and α-esterase levels. The effects enhanced with the use of DFB-V, causing a significant decrease in α-esterase (7.7-fold) and an increase in monooxygenases (7.8-fold) ( < 0.05) in AND- compared to the wild-caught strain. The variation in enzyme levels in the two strains may be due to the stress caused by insecticides of different chemical natures used in the fields. No negative effects were observed on the non-target organisms-, , and .
The studies showed the growth regulatory efficacy of DFB and probable role of GST and α-esterases in increasing the effects of DFB when synergized with verapamil. Further, the DFB-V combination did not result in any significant negative effects on the non-target organisms ascertaining its safe use. This is the first report unraveling the effects of the DFB-verapamil combination on the defense mechanism of Further studies may assist in developing focused and eco-safe plans for managing populations effectively.
作为多种虫媒病毒疾病的传播媒介，在全球范围内是主要的健康关注点。虫媒疾病的激增凸显了采取有效病媒控制措施的迫切需求。然而，传统使用的合成农药存在环境问题以及诸如抗药性发展等问题，导致需要使用更高的化学剂量。因此，诸如使用昆虫生长调节剂（除虫脲；DFB）等替代干预措施因其独特的作用机制和环境安全性而展现出前景。尽管如此，蚊子有可能对任何化学物质产生抗性。因此，本研究调查了DFB与维拉帕米联合使用（DFB-V；1:10）作为一种可能的蚊虫干预措施。
评估了DFB和DFB-V对实验室饲养（AND-）和野外捕获（GVD-）品系的幼虫发育、成虫羽化以及解毒酶、非特异性酯酶、谷胱甘肽S-转移酶（GST）、乙酰胆碱酯酶（AChE）和单加氧酶表达的影响。还研究了对非靶标生物存活的影响。
研究表明，用DFB-V处理四龄幼虫导致成虫羽化抑制比单独使用DFB高1.16 - 1.37倍，降低了IE值。DFB处理增加了β-酯酶、AChE和单加氧酶，但降低了GST和α-酯酶水平。与野外捕获品系相比，使用DFB-V增强了这些影响，导致AND-品系中α-酯酶显著降低（降低7.7倍）和单加氧酶增加（增加7.8倍）（P < 0.05）。两个品系中酶水平的差异可能是由于田间使用的不同化学性质杀虫剂所造成的压力。未观察到对非靶标生物（[具体生物名称未给出]）有负面影响。
研究表明了DFB的生长调节功效以及GST和α-酯酶在与维拉帕米协同作用时增强DFB效果方面可能发挥的作用。此外，DFB-V组合对非靶标生物未产生任何显著负面影响，确定了其安全使用性。这是首篇揭示DFB - 维拉帕米组合对决[具体蚊虫名称未给出]防御机制影响的报告。进一步的研究可能有助于制定针对性强且生态安全的计划，以有效管理[具体蚊虫名称未给出]种群。
