Lifetime Fitness of Hybrids in Natural Plant Populations: Testing Models for Hybrid Zones

自然植物种群中杂交品种的终生适应性：杂交区模型测试

• 批准号: 9806547
• 负责人: Diane Campbell
• 金额: $ 20万
• 依托单位: Rocky Mountain Biological Laboratory
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9806547&HistoricalAwards=false
• 关键词: Lifetime; Fitness; Hybrids; Natural; Plant

Campbell 9806547 Hybrid zones are areas where related species, or other genetically distinct populations, come together and produce some viable offspring. Hybridization is particularly widespread in flowering plants and also occurs in many animal groups. Evolutionary biologists propose several models to explain patterns of genetic variation across the resulting hybrid zones. These models differ in the assumptions they make about natural selection on hybrids, and they have different important consequences for long-term evolution. Understanding the processes responsible for maintaining hybrid zones can also be applied to prevention of hybridization between crops and related weeds, and to conservation of rare species that occur near more common relatives. This study will test models for hybrid zones by comparing the lifetime fitness of parent and hybrid plants in the field. The investigators will follow the survival and final reproductive success of offspring generated from experimental crosses between two closely related species, Ipomopsis aggregata and Ipomopsis tenuituba, and planted as seeds into several locations. First generation and second generation hybrids will be planted. Each model can be distinguished by its unique predictions about the fitnesses of hybrids and parental individuals and how these change across environments. In addition, the investigators will determine whether interactions between pollen grains of the two species can reduce the level of hybrid formation and contribute to geographical variation in the extent of hybridization. This goal will be met using experiments and computer simulations to determine the mixtures of pollen that reach flowers in natural populations, and by performing experimental pollinations and genetic analysis of seeds.

坎贝尔9806547混合区是相关物种或其他遗传学种群的区域，它们聚集在一起并产生一些可行的后代。杂交在开花植物中尤为广泛，并且在许多动物群中也发生。 进化生物学家提出了几种模型来解释在所得杂种区域之间遗传变异的模式。 这些模型在他们对杂种自然选择的假设上有所不同，它们对长期进化产生了不同的重要后果。 了解负责维持杂种区域的过程也可以应用于预防农作物与相关杂草之间的杂交，并保存在更常见的亲戚附近发生的稀有物种。 这项研究将通过比较田间的父母和杂种植物的寿命适应性来测试混合区域的模型。 研究人员将遵循从两个密切相关的物种（ipomopsis cotregata和tenuituba）之间实验十字产生的后代的生存和最终生殖成功，并将种子作为种子种植到多个位置。 将种植第一代和第二代杂种。每个模型都可以通过其关于混合体和父母个体的适应性以及这些方式在环境中发生变化的独特预测来区分。 此外，研究人员将确定两个物种花粉颗粒之间的相互作用是否可以降低杂交形成水平，并导致杂交程度的地理变异。将使用实验和计算机模拟来实现此目标，以确定在天然种群中花粉的混合物，并通过对种子进行实验授粉和遗传分析。

项目成果

Early snowmelt projected to cause population decline in a subalpine plant

• DOI: 10.1073/pnas.1820096116
• 发表时间: 2019-06-25
• 期刊: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• 影响因子: 11.1
• 作者: Campbell, Diane R.