Terpenoid Defences in Spruce (Picea spp.)

云杉是加拿大森林工业中最具经济价值的树种之一;它们在加拿大的许多森林生态系统中占主导地位，对亚洲和欧洲的森林经济也至关重要。随着环境的变化，云杉和其他针叶树越来越受到害虫和病原体爆发的挑战。可持续森林管理需要对树木的自然防御和抵抗机制有深入的了解。在与害虫和病原体共同进化的数亿年中，针叶树已经进化出被称为松脂（沥青）的主要化学防御。油树脂是在树脂导管或水泡中形成的数百种专门代谢物（萜类化合物）的复杂混合物。它主要由二萜树脂酸（松香）和挥发性单萜（松节油）组成。油树脂的化学多样性是由基因和酶产生的，这些基因和酶被称为萜烯脱氢酶和细胞色素P450。针叶树积累松脂作为预先形成的或昆虫/病原体诱导的防御。油树脂和其他化学品为针叶树提供持久的保护，使其免受大多数潜在害虫或病原体的侵害。虽然一些高度破坏性的害虫（例如，象鼻虫、树皮甲虫、芽虫）可以压倒或破坏树木的防御，即使在这些系统中也观察到了独特的树木抗性。例如，在锡特卡云杉的选择基因型中鉴定了对象鼻虫的抗性。我关于云杉对抗象鼻虫的长期研究计划建立了一个领域定义系统，用于油树脂/萜类化合物防御的基因组学支持的分子表征。我的计划提供天然树木防御机制的领先知识，这是与加拿大和国际森林管理组织合作，以实现经济和生态效益。除了林业，萜类化合物对许多生物产品行业（食品、调味品、香料、生物农药、制药）和先进的生物燃料也具有巨大的价值。我的萜类生物化学课程为这些行业的应用提供了先进的知识和技术。我的项目为本科生、研究生、博士后和技术人员提供了极好的培训机会。

Species of spruce are among the most economically important trees for Canada's forest industry; they dominate many of the forest ecosystems across Canada, and are also of critical importance to forest economies in Asia and Europe. With environmental change, spruce and other conifers are increasingly challenged by outbreaks of insect pests and pathogens. Sustainable forest management requires advanced knowledge of trees' natural defence and resistance mechanisms. In hundreds of millions of years of co-evolution with pests and pathogens, conifers have evolved major chemical defences known as oleoresin (pitch). Oleoresin is a complex mixture of hundreds of specialized metabolites (terpenoids) formed in resin ducts or blisters. It consists mostly of diterpene resin acids (rosin) and volatile monoterpenes (turpentine). The chemical diversity of oleoresin is produced by genes and enzymes known as terpene synthases and cytochrome P450s. Conifers accumulate oleoresin as preformed or insect/pathogen-induced defences. Oleoresin and other chemicals provide durable protection for conifers against most potential pests or pathogens. While some highly destructive pests (e.g., weevils, bark beetles, budworms) can overwhelm or undermine tree defences, even in these systems unique tree resistance has been observed. For example, resistance against weevils was identified in select genotypes of Sitka spruce. My long-term research program on spruce defence against weevils established a field-defining system for a genomics-enabled, molecular characterization of oleoresin/terpenoid defences. My program delivers leading knowledge on natural tree defence mechanisms, which is being applied in collaboration with Canadian and international forest stewardship organizations for economic and ecological benefits. Beyond forestry, terpenoids are also enormously valuable for many bio-product industries (food, flavour, fragrance, bio-pesticides, pharmaceuticals) and as advanced biofuels. My program on terpenoid biochemistry delivers advanced knowledge and technology for applications in these industries. My program provides excellent training opportunities for undergraduate and graduate students, postdoctoral trainees, and technicians.