Novel viral insecticides for forest protection in the age of climate change

随着气候变化，预计森林生态系统将受到越来越多的干扰，包括范围扩大和害虫的生存。不仅本土昆虫的范围将扩大，而且一些昆虫预计将进一步向北扩展到加拿大。如果不加以控制，这将不可避免地导致更多的落叶破坏，从而影响其中物种的生物多样性，并严重影响每年为我们的贸易差额贡献约300亿美元的林业。加拿大可以选择什么都不做。或者，它可以选择积极主动地制定战略，如何最好地保护我们宝贵的加拿大森林资源和碳汇，为这一不可避免的情况做准备。我们的建议解决了针对特定森林害虫的替代生物害虫控制剂的需求，方法是利用以病毒为基础的杀虫剂的许多优点(特异性、易于生产、生态系统固有的)，但对其进行修改以使其更有效。特别是，我们正在开发一种平台技术，即病毒重新编程，以使任何杆状病毒更加有效。两种病毒酶，几丁质酶和组织蛋白酶，通常在病毒感染期间产生，用来破坏患病昆虫的结构完整性，导致它真正液化。我们重新编程的本地病毒将被设计成在感染后的早期产生更多的这两种酶。我们预计幼虫将比正常情况下更早死亡，从而减少对摄食的损害。为了做出这些改变，我们将使用病毒自身的基因控制元件来实现这种重新编程。虽然最初的目标是针对云杉芽孢子虫的杆状病毒，但这种平台技术很容易扩展到其他森林(和农业)害虫物种。我们也意识到新的害虫将扩展到加拿大森林，本地害虫的范围将会增加，我们还将开发一组昆虫细胞系，以

With climate change increased perturbations of the forest ecosystem are expected, including range expansion and survival of insect pests. Not only would there be an expanded range of native insects but also some insects are expected to expand further northward into Canada. If left unchecked this will inevitably lead to increased defoliation damage thereby impacting the biodiversity of the species within them and significantly affecting the forestry industry which contributes about $30 billion annually to our balance of trade. Canada could choose to do nothing. Or it could choose to be proactive and devise strategies on how best to preserve our valuable Canadian forest resource and carbon sink in preparation for this inevitability. Our proposal addresses the need for alternative, biological, insect pest control agents, targeted to specific forest pests by harnessing the many advantages of viral based insecticides (specificity, ease of production, native to the ecosystem), but modified to make them more effective. In particular we are developing a platform technology, virus reprogramming, to make any baculovirus more effective. Two virus enzymes, chitinase and cathepsin, normally produced during virus infection, serve to destroy the structural integrity of the diseased insect causing it to literally liquefy. Our reprogrammed native viruses will be designed to produce greater amounts of these two enzymes and at earlier times after infection. We expect the larvae to be killed earlier than normal, thereby reducing feeding damage. To make these changes we would use the virus's own genetic control elements to effect this reprogramming. While initially targeting a baculovirus against the spruce budworm this platform technology could easily be expanded to other forest (and agricultural) insect pest species. Recognizing also that new pests will expand into the Canadian forest and range of native ones will increase, we will also develop a panel of insect cell lines to a