Mapping non-targeted-site resistance to herbicides in Spirodela polyrhiza (MapNTSR)

植物对环境变化的适应性进化-无论是自然的还是人为的-塑造了全球生物多样性，并能深刻影响人类社会的发展。一个典型的例子是杂草对除草剂的抗药性迅速增加，这威胁到世界范围内的作物产量。除草剂抗性机制分为两种类型：靶点抗性（TSR），由除草剂靶蛋白的变化引起，和非靶点抗性（NTSR），包括所有其他机制。最近的研究表明，NTSRs来自与适应自然压力有关的长期遗传变异。然而，由于缺乏一个合适的模型系统，详细的分子机制和生态功能的NTSR的特点，这一假设仍然在很大程度上未经检验。在这里，我们将使用巨大的浮萍，螺旋藻polyrhiza，作为一个模型系统，调查草甘膦和敌草快，两个广泛使用的除草剂，这被认为是主要由NTSR引起的抗性。我们将结合联合收割机全基因组关联方法和基因共表达网络分析，以确定耐药性的遗传基础。此外，使用最先进的基因组编辑工具（CRISPR/Cas9），我们将操纵已鉴定的候选基因，并研究巨型浮萍中NTSR的潜在分子机制。此外，我们将评估NTSR相关基因的变化在多大程度上影响对自然胁迫的抗性。这项综合性研究将弥合理解除草剂适应的分子机制，过程和后果的知识差距，并促进新战略的发展，以改善杂草管理。

Adaptive evolution of plants to environmental change – either natural or human-mediated - shaped the global biodiversity and can profoundly affect the development of human societies. A classic example is the rapid increase of herbicide resistance in weeds, which threatens worldwide crop yields. The mechanisms of herbicide resistance mechanisms are classified into two types: target-site resistance (TSR), which is caused by changes in the herbicide target protein, and non-target site resistance (NTSR), which includes all other mechanisms. Recent studies suggested that NTSRs arises from standing genetic variations that are associated with adaptation to natural stresses. However, due to the lack of a suitable model system in which the detailed molecular mechanisms and ecological functions of NTSR can be characterized, this hypothesis remains largely unexamined. Here, we will use the giant duckweed, Spirodela polyrhiza, as a model system to investigate the resistance to glyphosate and diquat, two extensively used herbicides, which are considered to be predominantly caused by NTSR. We will combine a genome-wide association approach and gene co-expression network analyses to identify the genetic basis underlying the resistance. Furthermore, using a state-of-the-art genome editing tool (CRISPR/Cas9), we will manipulate the identified candidate genes and investigate the underlying molecular mechanisms of the NTSR in the giant duckweed. Additionally, we will evaluate to what extent changes of the genes involved in NTSR affect the resistance to natural stresses. This integrative study will bridge a knowledge gap in understanding the molecular mechanisms, processes and consequences of adaptation to herbicides and facilitate the development of new strategies to improve weed management.