EAGER: The relative contributions of pollen and seed dispersal to gene flow and propagule survival in a tropical palm

EAGER：花粉和种子传播对热带棕榈基因流和繁殖体存活的相对贡献

• 批准号: 1548548
• 负责人: Jordan Karubian
• 金额: $ 20万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-10-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1548548&HistoricalAwards=false
• 关键词: EAGER; relative; contributions; pollen; seed

Many plants rely on animals to pollinate their flowers and disperse their seeds. These services are important because most plants are literally rooted in place, with animals providing one of their only opportunities to colonize new places. Ecologists are especially interested in the relative importance of seed dispersal and pollination. If, for example, seed dispersal is more important than pollination, then declines in seed disperser populations will have greater ecological impacts than declines in pollinators. This project will use genetic techniques and field experiments to test the impact of pollinators and seed dispersers on the ability of a tropical tree to grow and survive under conditions near and far from parent trees of the same species. The researchers will integrate their work with education and sustainable development programs that are designed to improve conservation outcomes in the study area, a biodiversity hotspot in Ecuador. The project will provide training for undergraduates, graduate students and post-doctoral fellows, and will use public presentations, websites, film and video to communicate results to the public.The study design combines correlative data from the field with experiments and molecular analyses to address how seed dispersal mediates the initial pattern of gene flow achieved by pollination and to investigate how patterns of mortality shape the relative contribution of pollen vs. seed dispersal at successive life stages. The particular focus is on how genetic 'uniqueness' of a dispersed seed (i.e., the seed's genotype relative to the existing genetic background of all other seeds nearby) may influence its survival. The study system is an animal-dispersed tropical palm, Oenocarpus bataua, in northwest Ecuador. The working hypotheses are that: (1) long distance seed dispersal will promote gene flow by introducing novel male gametic genotypes into seed pools; (2) after controlling for dispersal distance and density, genetic uniqueness will be associated with increased seed and seedling survival; and, (3) the relative contribution of seed dispersal to realized gene flow will increase across successive life stages. Dispersal kernels will be calculated for both pollen and seeds via molecular analyses. Survival of naturally dispersed seeds will be analyzed in relation to dispersal distance, conspecific density, and genetic uniqueness. A complementary, field-based reciprocal transplant experiment will manipulate genetic uniqueness and dispersal distance of seeds, then provide data on subsequent growth and survival of seedlings. Finally, genetic structure will be compared across multiple age classes, from seed to adult. Many students will be mentored in research. Results will be disseminated through a blog and a YouTube channel, and incorporated into a field course.

许多植物依靠动物为其花朵授粉并传播种子。这些服务很重要，因为大多数植物实际上都扎根于某个地方，而动物提供了它们在新地方定居的唯一机会之一。 生态学家对种子传播和授粉的相对重要性特别感兴趣。 例如，如果种子传播比授粉更重要，那么种子传播者数量的减少将比传粉媒介的减少产生更大的生态影响。 该项目将利用遗传技术和田间实验来测试传粉者和种子传播者对热带树木在远离同一物种亲本树的条件下生长和生存的能力的影响。 研究人员将把他们的工作与教育和可持续发展计划结合起来，这些计划旨在改善厄瓜多尔生物多样性热点研究区的保护成果。该项目将为本科生、研究生和博士后提供培训，并将利用公开演示、网站、电影和视频向公众传达结果。研究设计将现场的相关数据与实验和分子分析相结合，以解决种子传播如何介导通过授粉实现的基因流的初始模式，并研究死亡率模式如何影响连续生命阶段花粉与种子传播的相对贡献。特别关注的是分散种子的遗传“独特性”（即种子的基因型相对于附近所有其他种子的现有遗传背景）如何影响其生存。该研究系统是厄瓜多尔西北部的一种动物分散的热带棕榈树 Oenocarpus bataua。工作假设是：（1）长距离种子传播将通过将新的雄性配子基因型引入种子库来促进基因流动； (2) 在控制扩散距离和密度后，遗传独特性将与种子和幼苗存活率的提高相关； (3)种子传播对实现的基因流的相对贡献将在连续的生命阶段中增加。将通过分子分析计算花粉和种子的传播粒。自然传播种子的存活率将根据传播距离、同种密度和遗传独特性进行分析。互补的、基于田间的互惠移植实验将操纵种子的遗传独特性和传播距离，然后提供有关幼苗随后生长和存活的数据。最后，将比较从种子到成年的多个年龄段的遗传结构。 许多学生将得到研究指导。 结果将通过博客和 YouTube 频道传播，并纳入实地课程。