The ecology of alien insect herbivores

我的研究项目涉及影响外来入侵昆虫物种在农业系统中的建立、传播和种群增长的因素，包括它们的生活史特征和与寄主植物的相互作用。外来入侵物种对农业和自然生态系统构成相当大的威胁，影响生态系统的完整性并造成重大的经济损失。我研究计划的下一阶段将集中在瑞典蠓种群动态及其与宿主植物的相互作用的几个未经研究的方面。我于2000年首次记录了瑞典蠓在安大略省的存在，从那时起，它在安大略省和魁北克省迅速蔓延。这种小苍蝇以十字花科植物为食并在其上发育，并导致瘿的形成以及叶、茎和开花组织的畸形。在安大略省，高水平的虫害导致一些田地的西兰花和油菜籽完全减产。瑞典蠓的生活史特征，如可能出现多种羽化表型和较长的滞育期，可能是其成功入侵的重要因素。这些生活史特征将被研究，并确定它们对瑞典蠓潜在种群增长和地理范围扩大的影响。本研究计划的另一个方面将是确定瘿形成的过程，确定瘿形成的因素，并首次记录对瑞典蠓感染敏感和抗性的寄主植物之间瘿发育的形态和生理差异。这项研究将提高我们准确预测瑞典蠓种群动态的能力，也可能导致抗性作物品种的开发，从而减少农药的使用，促进采用生态无害的害虫管理措施。

My research program involves examination of factors affecting the establishment, spread and population growth of invasive alien insect species in agricultural systems, including their life history traits and interactions with host plants. Invasive alien species represent a considerable threat to agricultural and natural ecosystems, impacting ecosystem integrity and causing major economic losses. The next phase of my research program will focus on several unexamined aspects of the population dynamics of the swede midge and interactions with its host plants. I first documented the presence of the swede midge in Ontario in 2000, and it has spread rapidly throughout Ontario and Quebec since then. This small fly feeds and develops on cruciferous plants and causes the formation of galls and malformation of leaf, stem and flowering tissues. High levels of infestation in Ontario have led to the complete loss of broccoli and canola harvests in some fields. Life history characteristics of the swede midge, such as the possible occurrence of multiple emergence phenotypes and prolonged diapause, may be significant factors in its success as an invasive species. These life history characteristics will be examined and their impact on potential population growth and geographic range expansion of the swede midge will be determined. Another aspect of this research program will be determining the process of gall formation, determining what factors are responsible for gall initiation, and for the first time documenting the morphological and physiological differences in gall development between host plants that are susceptible and resistant to swede midge infestation. This research will improve our ability to accurately predict swede midge population dynamics and may also lead to the development of resistant crop varieties, thus reducing pesticide use and facilitating the adoption of ecologically-sound pest management practices.