Collaborative Research: Developmental Ecology of Mayapple

合作研究：Mayapple的发育生态学

• 批准号: 9409395
• 负责人: Maxine Watson
• 金额: $ 31.05万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-12-01 至 2000-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9409395&HistoricalAwards=false
• 关键词: Collaborative; Research; Developmental; Ecology; Mayapple

9409395 Watson Persistence of plant populations in nature is partly due to their success at sexual reproduction --i.e., their production of seeds. Among the determinants of plant reproductive success are (1) their schedules of reproduction through time, or life histories, and (2) the amount of resources available to them at critical points in the expression of these life histories. Because plants grow and reproduce by building new leaves and flowers, the expression of a plant's life history is the result of on-going developmental decisions about the type of structures it makes. And because a structure cannot both be vegetative and flowering, there is an inherent trade-off between plant growth and reproduction. The trade-off between growth and reproduction is complicated be the interaction between (1) the expression of the plant's developmental program, which specifies when and what type of new structures may be made, and (2) the efficiency of a particular type of structure in resource accumulation. Some structures will add to the plant's future growth potential, others detract, thus influencing the course of subsequent development and reproductive success. In producing vegetative structures, for example, plants may increase their lifetime seed production through increases in plant size and vigor. Little is known about how the interaction between developmental program and resource use actually results, mechanistically, in the expression of a particular life history. The interactions between developmental program, seasonal patterns of resource uptake and use, and life history in the herbaceous perennial, mayapple (Podophyllum peltatum) will be studied. Mayapple is an ideal plant for such studies because each year its rhizome faces a simple developmental decision whether to produce a reproductive shoot or a single leaf; only one such structure is made. Longterm studies of native populations are used to (1) construct a developmental timetable for shoot type determination, (2) examine the interaction between the degree and pattern of resource uptake and use and shoot determination, and (3) determine whether differences in the timing of developmental events, as manifested by different clones, affect longterm demography and, hence, fitness. This study also will reveal at what points selection may act to alter the timing of developmental events, thus contributing to understanding of how different life histories evolve -- a critical issue for plants facing rapidly changing environments, as well as for the modification of crop plants for higher productivity.

9409395 Watson 植物种群在自然界中的持久存在部分归因于它们在有性繁殖方面的成功——即它们产生种子。 植物繁殖成功的决定因素包括（1）它们在时间或生命史中的繁殖时间表，以及（2）在这些生命史表达的关键点上可供它们使用的资源量。 由于植物通过长出新的叶子和花朵来生长和繁殖，因此植物生命史的表达是对其所形成的结构类型进行持续发育决策的结果。 而且由于一个结构不可能既营养又开花，因此植物生长和繁殖之间存在固有的权衡。 生长和繁殖之间的权衡很复杂，因为（1）植物发育程序的表达，它指定了何时以及可以制作什么类型的新结构，以及（2）特定类型结构在资源积累中的效率。 一些结构会增加植物未来的生长潜力，而另一些结构则会减弱，从而影响随后的发育和繁殖成功的过程。 例如，在产生营养结构时，植物可以通过增加植物大小和活力来增加其生命周期的种子产量。 人们对发展计划和资源利用之间的相互作用实际上如何机械地导致特定生活史的表达知之甚少。 将研究多年生草本鬼臼植物（Podophyllum peltatum）的发育计划、资源吸收和使用的季节性模式以及生活史之间的相互作用。 山梨树是此类研究的理想植物，因为每年它的根茎都会面临一个简单的发育决定，是产生生殖芽还是单叶；仅制作了一个这样的结构。 对本地种群的长期研究用于（1）构建确定芽类型的发育时间表，（2）检查资源吸收和使用的程度和模式与芽确定之间的相互作用，以及（3）确定不同克隆所表现的发育事件时间的差异是否影响长期人口统计学，从而影响适应性。 这项研究还将揭示选择在什么时候可能会改变发育事件的时间，从而有助于理解不同的生命史如何进化——这对于面临快速变化环境的植物以及为提高生产力而改造农作物来说是一个关键问题。