Collaborative Research: Developmental Ecology of Mayapple

小行星9410086 一种植物是否能够在特定的自然环境中生存，取决于它在进化过程中的繁殖成功率或适应性。 繁殖成功的决定因素包括繁殖时间表，即生活史和可用于繁殖的资源。 由于植物的繁殖成功直接受到繁殖结构（花）数量的影响，植物面临着生产立即增加繁殖输出的花与生产新的营养结构（叶和根）之间的权衡，这些营养结构增强资源吸收并可能导致植物生命中更高的繁殖成功。 这种权衡是复杂的相互作用之间的（1）植物的内在发展计划，这影响什么时候和什么类型的新结构将作出，和（2）的效率，该结构在资源积累，这反过来又影响植物的后续发展计划。 植物的发育程序和资源积累之间的这种相互作用对种群中生殖个体的比例的影响，即种群的人口统计学，知之甚少。 本研究将探讨多年生草本无性系植物梅果（Podophyllum peltatum）的发育程序、资源吸收与利用以及人口统计学之间的相互作用。 Mayapple是这种研究的理想植物，因为每年每个根茎都面临一个简单的发展决定-产生一个单一的叶子，或者一个简单的生殖枝，上面有一朵花和两个叶子。 对自然发生种群的长期研究将用于（1）构建一个美洲梨发育决策的时间表，强调如何以及何时确定新的空中“芽”的类型，（2）检查过去获得的资源与当年获得的资源之间的相互作用，以确定当前和未来的芽类型;确定不同克隆之间发育事件的时间差异是否会影响其长期的生殖输出。 这项研究的结果将揭示发展时间和资源吸收的变化如何影响人口统计学。 此外，这项研究将揭示在什么时候选择可能会改变表达的发育程序的时间，从而有助于我们了解不同的生活史如何演变，这是植物面临快速变化的环境的一个关键问题。 这些结果将有助于了解如何在发展的时间变化影响营养和生殖生产力的重要经济植物以及。

9410086 Jones Whether a plant is able to persist in a particular natural environment is determined by its reproductive success, or fitness, through evolutionary time. Among the determinants of reproductive success are the schedule of reproduction, i.e. the life history, and the resources available for reproduction. Because a plant's reproductive success is directly influenced by the number of reproductive structures (flowers), plants face a tradeoff between producing flowers that increase reproductive output immediately, versus producing new vegetative structures (leaves and roots) that enhance resource uptake and may lead to higher reproductive success over the life of the plant. This tradeoff is complicated by the interaction between (1) a plant's inherent developmental program, which influences when and what type of new structure will be made, and (2) the efficiency of that structure in resource accumulation, which in turn influences the plant's subsequent developmental program. The influence of this interaction between a plant's developmental program and resource accumulation on the proportion of reproductive individuals in the population, i.e. the population's demography, is poorly understood. Interactions between developmental program, resource uptake and use, and demography in an herbaceous perennial clonal plant, mayapple (Podophyllum peltatum) will be examined. Mayapple is an ideal plant for such a study because each year each rhizome faces a simple developmental decision--to produce either a single foliage leaf, or a simple reproductive shoot bearing a single flower and two foliage leaves. Long-term studies of naturally occurring populations will be used to (1) construct a timetable of developmental decisions for mayapple, emphasizing how and when the type of new aerial "shoot" is determined, (2) examine the interaction between resources acquired in the past and those acquired in the current year on current and future determination of shoot type and (3) determine whether dif ferences in the timing of developmental events among different clones affects their reproductive output over the long term. The results of this study will reveal how variation in developmental timing and resource uptake affect demography. Moreover, this study will reveal at what points selection may act to alter the timing of the expressed developmental program, thus contributing to our understanding of how different life histories evolve, a critical issue for plants facing a rapidly changing environment. These results will contribute to understanding how variation in developmental timing affects vegetative and reproductive productivity in economically important plants as well.