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

植物对自然或人为环境变化的适应性进化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的抗除草剂能力迅速增强，这威胁到全世界的作物产量。除草剂抗性机制分为两类：一类是由除草剂靶蛋白变化引起的靶位点抗性（TSR），另一类是包括所有其他机制的非靶位点抗性（NTSR）。最近的研究表明，ntsr源于与适应自然压力相关的长期遗传变异。然而，由于缺乏合适的模型系统来表征NTSR的详细分子机制和生态功能，这一假设在很大程度上仍未得到验证。本文将以巨型浮萍Spirodela polyrhiza为模型系统，研究其对草甘膦和diquat的抗性，这两种被广泛使用的除草剂被认为主要是由NTSR引起的。我们将结合全基因组关联方法和基因共表达网络分析来确定抗性的遗传基础。此外，使用最先进的基因组编辑工具（CRISPR/Cas9），我们将操纵已确定的候选基因，并研究巨型浮萍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。这项综合研究将在理解除草剂适应的分子机制、过程和后果方面弥合知识差距，并促进制定新的策略来改善杂草管理。

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.