Advances in control technologies for wood-boring invasive insects

蛀木昆虫已成为加拿大森林健康最具威胁的生物制剂。以绿灰螟（EAB）、亚洲长角甲虫（ALB）、褐云杉长角甲虫（BSLB）和山松甲虫（MPB）等为例，这些昆虫对害虫管理行业构成了巨大的挑战。未成熟阶段的隐蔽生活方式，在树皮下度过，使得表面施用农药无效。由于它们的分散能力或缺乏摄食，成虫阶段同样不适合控制。在实践中，只有在高价值树木中通过树干注射杀虫剂制剂才能控制其中一些物种（例如EAB）。然后，这些杀虫剂系统地分布在树内，杀死吞食它们的昆虫幼虫。目前的项目旨在评估一种新型活性成分的商业潜力，这种活性成分被称为双链RNA (dsRNA)，可以对抗蛀木昆虫。DsRNA分子以序列特异性的方式减少基因表达。利用模式昆虫（果蝇）或攻击作物的昆虫进行的实验室测试表明，dsRNA具有高度的物种特异性活性。在林业中使用杀虫剂时，环境安全是最重要的，这将使dsRNA分子与其他特异性较低的化合物相比具有优势。我们将与biofforest Technologies Inc.合作，测试几个参数来评估dsRNA分子对抗木蛀虫的效果，包括dsRNA序列、剂量、配方、树木转运以及与现有给药系统的兼容性。这项研究将为biofforest技术公司提供dsrna作为新一代环境安全、物种特异性杀虫剂的潜力评估，这将有助于保护加拿大森林和公园树木免受一些最具破坏性的害虫的侵害。

Wood-boring insects have gained pre-eminence as the most threatening biotic agents to the health of Canadian forests. Exemplified by species such as the Emerald Ash Borer (EAB), the Asian long horned beetle (ALB), the Brown Spruce long horned beetle (BSLB) and the Mountain Pine Beetle (MPB), these insects pose a formidable challenge for the pest management industry. The cryptic lifestyle of immature stages, spent under the bark, makes surface application of pesticides ineffective. Adult stages are likewise unsuitable for control due to their dispersal ability or lack of feeding. In practice, the control of some of these species (e.g. EAB) is possible only in high value trees by the delivery of insecticide formulations via trunk injection. Such insecticides then systemically distribute within the tree and kill insect larvae that ingest them. The current project seeks to evaluate the commercial potential of a novel class of active ingredient, known as double-stranded RNA (dsRNA) against wood-boring insects. DsRNA molecules act by reducing gene expression in a sequence-specific manner. Lab tests using model insects (Drosophila) or insects attacking crops have demonstrated the highly species-specific activity of dsRNA. Translated to the context of insecticide use in forestry, where environmental safety is paramount, this would place dsRNA molecules at an advantage versus other compounds that are less specific. In partnership with BioForest Technologies Inc. we will test several parameters to evaluate the efficacy of dsRNA molecules against wood borers, including dsRNA sequence, dose, formulation, tree translocation and compatibility with existing delivery systems. This research will provide BioForest Technologies Inc. with an assessment of the potential of dsRNAs to serve as a new generation of environmentally-safe, species-specific insecticides, which could help protect Canadian forest and parkland trees from some of our most damaging pest insects.