Host Plant Phenology and Insect Speciation

小行星9509125 许多昆虫物种仅限于以特定的寄主植物为食。 这种专门化是如何产生的，它是否是物种形成的必要条件，以及它是否需要地理隔离，都有待讨论。 当昆虫获得新的寄主植物时，重要的是要了解其机制和后果，原因有很多。 寄主植物利用的变化发生在自然群落中，因此是试图了解昆虫植物群落的起源/结构和昆虫物种多样性的地理格局的重要因素。 如果一种新的寄主植物在商业上很重要，其结果往往是产生一种新的害虫。 在现有害虫物种的情况下，这种寄主植物的变化可能导致不同植物上种群之间的遗传变异，需要新的管理做法。 因此，为了了解自然和管理的植物群落，必须了解昆虫转移到新的寄主植物的启动过程和最终后果。 在这项提议中，来自单一种群的昆虫将被置于七个不同的环境中进行操纵。 每种环境都由天然和新型宿主植物的不同组合组成。 三种环境包括新的和自然的主机，允许确定是否会发生分歧的主机专业化时，有潜在的自由昆虫运动的主机之间的物种。 其余的环境是检查过程中的主机专业化时，昆虫的自由移动之间的天然和新的寄主植物被禁止。 实验将在现场进行，使用28个大型屏蔽步入式房间。 这七个环境中的每一个都将被复制四次。 待检查的变量将是寄主植物物种对昆虫生活史卵孵化，交配和产卵时间的影响。 在这些生活史阶段的每个阶段，将确定不同的宿主对生存的影响。 将使用标记的昆虫来确定七种环境中每种环境中宿主之间的移动程度。

9509125 WOOD Many insect species are restricted to feed on specific host plants. How this specialization comes about, whether it is a requisite for speciation and whether it requires geographic isolation are open to debate. When insects acquire novel host plants it is important to understand the mechanisms and consequences, for a number of reasons. Changes in host plant usage occur in natural communities and thus are important factors in attempts to understand the origin / structuring of insect-plant communities and geographic patterns of insect species diversity. If a new host plant is commercially important, the result is often the creation of a new pest. In cases of existing pest species such host plant changes can lead to genetic alterations between populations on different plants that require new management practices. Thus to understand natural and managed plant communities the processes that initiate and the ultimate consequences of insect shifts to new host plants must be understood. In this proposal insects from a single population will be manipulated by placing them in seven different environments. Each environment consists of different combinations of natural and novel host plants. Three environments consist of novel and natural hosts which allows the determination of whether divergent host specialization can occur when there is potential free insect movement between host species. The remaining environments are to examine the process of host specialization when free insect movement between natural and novel host plants is prohibited. The experiment will be done in the field utilizing 28 large screened walk-in rooms. Each of the seven environments will be replicated four times. Variables to be examined will be host plant species effects on insect life history timing of egg hatch, mating, and egg deposition. At each of these life history stages differential host effects on survival will be determined. The extent of movement between hosts within each of the seven enviro nments will be determined using marked insects.