Phylogenetic relationships and reticulate evolution in Poa and subtribe Poinae

早熟禾和早熟禾亚族的系统发育关系和网状进化

• 批准号: 238614-2009
• 负责人: Gillespie, Lynn
• 金额: $ 1.24万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=478911
• 关键词: Phylogenetic; relationships; reticulate; evolution; Poa

The long-term objectives of my research program focus on understanding phylogenetic relationships and the influence of hybridization on the evolution in flowering plants. My research is focused primarily on the large grass tribe Poeae and the largest grass genus Poa, commonly known as bluegrass, as the model for these studies. Poa is one of the most taxonomically challenging genera of flowering plants; its complexity is thought to be due to extensive hybridization and polyploidy, further compounded by morphological reduction and the paucity of useful characters for identification. Our previous research successfully used molecular data to construct a framework of evolutionary relationships within Poa and among related genera. Using this phylogenetic hypothesis, along with a careful consideration of morphological characters, we recently presented a preliminary extensively revised classification scheme for Poa, the first with world-wide coverage for the genus. We made progress towards unraveling its complex history of intertwined lineages by identifying cases of ancient and relatively recent hybridization, both within Poa and between it and other genera. I now propose to test the robustness of our phylogenetic hypothesis and classification by sampling additional DNA regions and broadening the geographic and taxonomic coverage. Multiple taxonomic levels will be examined, from speciose groups within Poa up to the tribe level, and cases of hybridization will be identified and explored in detail. Our aims are ultimately to understand the evolutionary history, diversification, biogeography, morphological and breeding system evolution in this ecologically successful, species-rich group of plants, to provide a sound phylogenetic framework for worldwide revisions, and to further our understanding of reticulate evolution and hybrid origin in flowering plants Economically important as nutritious and palatable forage, lawn and pasture grass, soil stabilizers, and cover crops, information gained can also be useful in applied applications such as agronomy, land reclamation, and conservation management.

我的研究计划的长期目标侧重于了解系统发育关系以及杂交对开花植物进化的影响。 我的研究主要集中在大型禾本科早熟禾和最大的禾本科早熟禾属（俗称早熟禾）上，作为这些研究的模型。 早熟禾是分类学上最具挑战性的开花植物属之一。其复杂性被认为是由于广泛的杂交和多倍体，再加上形态的减少和用于识别的有用性状的缺乏，进一步加剧了这种复杂性。 我们之前的研究成功地利用分子数据构建了早熟禾属内部和相关属之间的进化关系框架。 利用这一系统发育假说，并仔细考虑形态特征，我们最近提出了早熟禾属的初步广泛修订的分类方案，这是该属第一个覆盖全球的分类方案。 通过识别早熟禾属内部以及它与其他属之间的古代和相对较新的杂交案例，我们在揭示其相互交织的谱系的复杂历史方面取得了进展。 我现在建议通过对额外的 DNA 区域进行采样并扩大地理和分类覆盖范围来测试我们的系统发育假设和分类的稳健性。 将检查多个分类水平，从早熟禾内的物种群体到部落水平，并将识别和详细探索杂交案例。 我们的最终目标是了解这一生态上成功、物种丰富的植物群的进化历史、多样化、生物地理学、形态和育种系统的进化，为全球范围内的修订提供良好的系统发育框架，并进一步了解开花植物的网状进化和杂交起源。 也可用于农学、土地复垦和保护管理等应用。