Invasion ecology of non-native forest insects

森林外来昆虫的入侵生态学

• 批准号: RGPIN-2018-04065
• 负责人: Pureswaran, Deepa
• 金额: $ 2.04万
• 依托单位: University of New Brunswick
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745984
• 关键词: Invasion; ecology; non; native; forest

My research investigates the ecological basis of invasiveness to understand why some non-native species grow and expand to high and damaging densities, while others persist at low densities. Successful interchange of insect invaders between Europe and North America occurs due to similarities in their forest and faunal composition. However, North America receives more successful invaders than the reverse. Using three forest insect systems, I will test whether the extent to which non-native species become invasive can be explained by their life history traits and interactions with the novel community, including host trees, congeners, niche-sharers, and natural enemies. 1) To evaluate reciprocal invasion potential, we will compare community interactions of spruce bark beetles, the European Ips typographus and North American Dendroctonus rufipennis, in their respective native and invaded ranges. We will test whether: i) reproductive success is higher on nave host species, ii) invasion success in the new range is favoured by niche-sharing congeners and mitigated by their natural enemies, and iii) there are barriers to gene flow among populations that result in pheromone races that differ in invasion potential. 2) To evaluate whether mating interactions with natives can slow down an invasion, we will test whether interspecific matings occur between the non-native brown spruce longhorn beetle, Tetropium fuscum, and its native congener, T. cinnamopterum. We will construct a library of molecular markers unique to each species that will allow us to screen individual Tetropium spp. specimens for hybrid genotypes in the field. Sequences of T. fuscum from different European populations will be compared to Canadian populations to determine whether divergence and/or introgression have occurred since the invasion. 3) To determine whether trophic interactions influence invasion potential in Europe and Canada, we will test whether interactions between i) insect-host tree, ii) insect-fungus and iii) fungus-host tree affect colonization potential of non-native ambrosia beetles, Xylosandrus germanus and Xylosandrus crassiusculus that differ in their invasiveness. Results from these studies will help build a community ecology framework to evaluate invasiveness of potential non-native species that have been intercepted and may establish in Canada.

我的研究调查了入侵的生态基础，以理解为什么一些非本地物种生长和扩展到高和破坏性的密度，而另一些则持续在低密度。由于欧洲和北美在森林和动物组成上的相似性，入侵昆虫在欧洲和北美之间的成功交换发生了。然而，北美收到的成功入侵者比相反的要多。利用三种森林昆虫系统，我将测试非本地物种成为入侵的程度是否可以用它们的生活史特征和与新群落的相互作用来解释，包括寄主树、同系物、生态位共享者和天敌。1)为了评价相互入侵的潜力，我们将比较云杉树皮甲虫、欧洲Ips typographus和北美rufipennis在其各自的原生和入侵范围内的群落相互作用。我们将测试：i)普通寄主物种的繁殖成功率是否更高；ii)在新范围内的入侵成功受到共享生态位的同族生物的青睐，并被它们的天敌所缓解；iii)种群间基因流动存在障碍，导致信息素种族在入侵潜力上存在差异。2)为了评估与本地物种的交配互动是否可以减缓入侵，我们将测试非本地褐云杉长角甲虫（Tetropium fuscum）与其本地同族物种T. cinnamopterum之间是否会发生种间交配。我们将构建每个物种独特的分子标记文库，这将使我们能够在野外筛选单个四足鼠标本的杂交基因型。来自不同欧洲种群的fuscum序列将与加拿大种群进行比较，以确定自入侵以来是否发生了分化和/或渗入。3)为了确定营养相互作用是否会影响欧洲和加拿大的入侵潜力，我们将测试i)昆虫-寄主树，ii)昆虫-真菌和iii)真菌-寄主树之间的相互作用是否会影响入侵性不同的非本地ambrosia甲虫、Xylosandrus germanus和Xylosandrus crassiusculus的定殖潜力。这些研究的结果将有助于建立一个群落生态学框架，以评估已经截获并可能在加拿大建立的潜在非本土物种的入侵性。