The evolution of development of flowering plant reproductive cycles

开花植物生殖周期发育的演变

• 批准号: 1052291
• 负责人: Joseph Williams
• 金额: $ 40.3万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1052291&HistoricalAwards=false
• 关键词: evolution; development; flowering; plant; reproductive

The great lability of their reproductive systems is central to the adaptability and rapid diversification of the flowering plants. With the origin of the group, ovules (future seeds) became enclosed within female tissues, necessitating a new site of pollen reception (the stigma) far removed from the site of fertilization (the egg). A critical innovation enabling this stigma-egg dissociation was the origin of a new pollen tube growth pattern in which sperm could be carried to the egg rapidly and through novel maternal tissues. The primary goal of this project is to understand the relationship between the evolution of pollen tube growth rates and reproductive cycles. The outcomes will bear on our understanding of ancient pollen-pistil interactions and floral biology, the focus of a great number of studies on more recently-evolved model and crop systems.The project will involve detailed and comprehensive quantitative characterizations of early and late pollen tube development in four angiosperm taxa that span the deepest divergences among extant angiosperms using in vivo and in vitro field and lab experiments. The goal is to identify underlying developmental causes of variation in pollen tube growth rates. These fine-scale mechanistic studies will be accompanied by broad-scale comparative analyses probing the relationship between pollen development and important ecological traits, such as the speed of reproduction, floral sizes and longevity, and vegetative metabolic rates.The PI has developed a synergistic teaching program in plant development and evolution that will provide graduate students with a focused intellectual environment. Training for a postdoctoral researcher and multiple undergraduate students is included. The project also features international collaborations, outreach, and teaching. The project bridges conceptual disciplines: the PI serves as a liaison between two NSF Research Coordination Networks, and is a founding board member of the Tennessee Plant Research Center. Outreach activities include public lectures and news media interviews.

它们的生殖系统的巨大不稳定性对于开花植物的适应性和快速多样化至关重要。随着群体的起源，胚珠（未来的种子）被封闭在雌性组织内，需要一个远离受精部位（卵子）的新花粉接收部位（柱头）。实现柱头与卵子分离的一项关键创新是新花粉管生长模式的起源，在这种模式下，精子可以通过新的母体组织快速携带到卵子。该项目的主要目标是了解花粉管生长速率的演变与生殖周期之间的关系。这些结果将影响我们对古代花粉-雌蕊相互作用和花卉生物学的理解，这是对最近进化的模型和作物系统的大量研究的重点。该项目将利用体内和体外现场和实验室实验，对四个被子植物类群的早期和晚期花粉管发育进行详细和全面的定量表征，这些类群跨越了现存被子植物之间最深的差异。目标是确定花粉管生长速率变化的潜在发育原因。这些精细的机制研究将伴随着大规模的比较分析，探讨花粉发育与重要生态特征之间的关系，例如繁殖速度、花的大小和寿命以及营养代谢率。 PI开发了植物发育和进化方面的协同教学计划，将为研究生提供一个集中的智力环境。包括对一名博士后研究员和多名本科生的培训。该项目还包括国际合作、外展和教学。该项目连接了概念学科：PI 充当两个 NSF 研究协调网络之间的联络人，并且是田纳西州植物研究中心的创始董事会成员。外展活动包括公开讲座和新闻媒体采访。