Evolutionary genomic approaches to understand the origin and maintenance biodiversity in forest and agricultural landscapes

进化基因组方法了解森林和农业景观的起源和维持生物多样性

• 批准号: RGPIN-2014-03634
• 负责人: Dayanandan, Selvadurai
• 金额: $ 1.75万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=565993
• 关键词: Evolutionary; genomic; approaches; understand; origin

Majority of plant species are considered to have derived from past hybridization events and the present hybridization may have positive or negative influence on the maintenance of biodiversity. Despite widespread occurrence of hybridization, its role in the origin and maintenance of biodiversity remains controversial. A detailed understanding of the past and present hybridization patterns in selected groups of plants is essential for gaining insights into the origin and maintenance of biodiversity. Phylogenetic analyses provide a means to infer past hybridization and reticulate evolution, and parentage analyses of selected plant populations using genotypic data are invaluable to infer the present hybridization levels. Therefore, it is crucial to have a robust phylogeny of an ecologically and morphologically diverse group of forest trees as a framework onto which morphological, biogeographical, ecological and genetic data can be super-imposed to elucidate evolutionary patterns and reticulate evolution. The forest tree genus Populus, the emerging model organism of tree biology research, with its wide geographic distribution, extensive hybridization, adaptability to a variety of habitats, many industrial applications and economic importance as a major source of wood, and the availability of extensive genetic, genomic and biochemical tools provides an ideal system to investigate the role of hybridization in evolution of biodiversity. We will i) reconstruct robust phylogenetic tree(s) of the genus Populus based on DNA sequences of nearly complete chloroplast and nuclear genomes, ii) develop species diagnostic molecular markers to identify the parentage of hybrids, and iii) determine the levels of hybridization and introgression in natural hybrid zones of selected Populus species. This research will capitalize on recent advances in high throughput genomics techniques to generate nearly complete sequences of the nuclear and chloroplast genomes to reconstruct phylogenetic trees, and high throughput genotyping technologies to genotype genome-wide single nucleotide polymorphism to determine the parentage of inter-specific hybrids at an unprecedented level of resolution. The resulting phylogenetic tree(s) will be used a) to test evolutionary hypotheses and reticulate evolution in poplars, and b) as a framework for systematic classification of taxa within the genus Populus. The resulting knowledge of the levels and directionality of introgression and parentage of hybrids will be valuable for a) understanding the genetic architecture and evolutionary dynamics of hybrid zones, and b) developing models to predict genetic consequences of hybridization between native and potentially invasive, non-native species. In addition, resulting species diagnostic molecular markers will serve as a tool for genome mapping and parentage identification in poplar breeding programs geared to address challenges in meeting wood and energy demands of the forest, paper pulp and biofuel industries under changing climatic conditions.

大多数植物物种被认为是从过去的杂交事件和目前的杂交可能会对生物多样性的维持产生积极或消极的影响。尽管杂交广泛存在，但其在生物多样性起源和维持中的作用仍存在争议。详细了解过去和现在的杂交模式，在选定的植物群体是至关重要的，深入了解生物多样性的起源和维护。系统发育分析提供了一种手段来推断过去的杂交和网状进化，和亲本分析选定的植物种群的基因型数据是非常宝贵的，以推断目前的杂交水平。因此，它是至关重要的，有一个强大的生态和形态多样性组的森林树木作为一个框架，形态，地理，生态和遗传数据可以叠加到阐明进化模式和网状进化。杨树属（Populus）是树木生物学研究的新兴模式生物，其广泛的地理分布、广泛的杂交、对多种生境的适应性、许多工业应用和作为木材主要来源的经济重要性，以及广泛的遗传学、基因组学和生物化学工具的可用性，为研究杂交在生物多样性进化中的作用提供了理想的体系。我们将i）基于几乎完整的叶绿体和核基因组的DNA序列重建稳健的杨树属系统发育树，ii）开发物种诊断分子标记以鉴定杂种的亲子关系，iii）确定所选杨树物种的天然杂交区中的杂交和渐渗水平。这项研究将利用高通量基因组学技术的最新进展，以产生几乎完整的核和叶绿体基因组序列，以重建系统发育树，和高通量基因分型技术基因型全基因组单核苷酸多态性，以确定在一个前所未有的分辨率水平的种间杂种的亲子关系。由此产生的系统发育树将被用于a）检验杨树的进化假设和网状进化，和B）作为杨树属内分类单元系统分类的框架。由此产生的杂交种的渐渗和亲子关系的水平和方向性的知识将是有价值的a）理解杂交区的遗传结构和进化动力学，和B）开发模型来预测本地和潜在入侵的非本地物种之间杂交的遗传后果。此外，由此产生的物种诊断分子标记将作为白杨育种计划的基因组作图和亲子鉴定的工具，以应对气候变化条件下满足森林，纸浆和生物燃料行业木材和能源需求的挑战。