REU: Genetically Variable Complex Life Cycles in Heterogeneous Environments

这项研究关注的是生活中变化的原因， 植物的周期。昆虫的取食。 蚜虫，>天疱疮> >甜菜>， 在其生命周期的一部分以棉白杨叶杨为食， 草本植物的根在其他部分。 一些殖民地 这些昆虫经常在这两种植物之间转换 而其他群落的转换频率较低。 初步证据 表明蚜虫之间的遗传差异部分是 负责主机切换频率的变化。 在 此外，环境因素，如温度和水平， 菌落中的拥挤促成了差异。 在这 在这项研究中，莫兰博士将研究这些不同的基因和 环境因素相互作用，以确定是否 蚜虫在寄主之间转换 此外，实验旨在 确定这些昆虫的生命周期是否以及如何 对寄主植物的遗传适应 有效性和寄主植物抗性。 比如莫兰医生 将决定蚜虫是否可以删除棉白杨相 三角叶棉白杨树所在地的生命周期 抗蚜虫攻击。 该项目也非常相关， 农业和林业害虫的实际管理。 研究结果将增加目前对植物喂养方式的理解 昆虫的进化是对它们的寄主植物的变异作出的反应。 农业害虫的这种进化反应 对农作物的经济影响有重要影响 以及设计长期虫害控制 战略布局

This study is concerned with causes of variation in the life cycles of plant.feeding insects. The aphid, >Pemphigus> >betae>, feeds on cottonwood trees during one part its life cycle and on roots of herbaceous plants at other parts. Some colonies of these insects switch between the two kinds of plants frequently while other colonies switch less often. Preliminary evidence suggests that genetic differences among aphids are partly responsible for the variation in frequency of host switching. In addition, environmental factors such as temperature and level of crowding in colonies contribute to the differences. In this study, Dr. Moran will examine how these different genetic and environmental factors interact to determine whether or not the aphids switch between hosts. Also, experiments are designed to determine whether and how life cycles of these insects are genetically adapted to local conditions of host plant availability and host plant resistance. For example, Dr. Moran will determine whether the aphids can delete the cottonwood phase of the life cycle in locations where the cottonwood trees are resistant to aphid attack. The project is also very relevant to the practical management of agricultural and forest pests. Findings will increase current understanding of how plant feeding insects evolve in response to variation in their host plants. Such evolutionary responses on the part of agricultural pests have important consequences for their economic impact on crops and forests and for the design of long.term pest control strategies.