Genomweite Assoziationsstudie für Trockentoleranz in Arabidopsis thaliana Keimlingen

干旱是影响植物的主要非生物胁迫。在全球范围内，水资源供应严重影响产量，这一问题可能会因气候变化而加剧。因此，培育更有效地利用水分并表现出更强抗旱性的作物植物是至关重要的。尽管利用传统育种或基因工程技术在培育抗旱植物方面取得了一些进展，但我们对自然界抗旱分子机制的了解仍然很差。一种鉴定天然植物抗旱新基因甚至基因网络的方法是全基因组关联研究（GWAS）。拟南芥是这类研究的理想工具，因为大量的基因分型材料（自然自交系）已经存在。自交系的可用性还有一个额外的好处，即基因型系可以多次用于表型分析，要么实现复制，要么研究基因型与环境的相互作用。我们的目标是对拟南芥幼苗的耐旱性进行GWAS研究，以确定该性状自然变异的主要决定因素。这种分析将导致识别在自然环境中相关的信号网络的许多假定的新组成部分。这些成分将通过杂交和转基因方法的组合使用进一步验证。最终的结果将是更好地了解有助于拟南芥和一般植物耐旱性的分子网络。

Drought is a major abiotic stress affecting plants. On a global scale, water availability affects yield severely, a problem that will likely be exacerbated by climate change. It is thus of fundamental importance to generate crop plants that utilize water more efficiently and show greater resistance to drought. Although some progress in generating drought resistant plants has been made using conventional breeding or genetic engineering, our understanding of the molecular mechanisms underlying drought resistance in nature is still very poor. One approach to identify new genes or even networks of genes contributing to drought tolerance in natural accessions is genome-wide association studies (GWAS). Arabidopsis thaliana is the ideal tool for this kind of study, as large collections of genotyped accessions (natural inbred lines) already exist. The availability of inbred lines has the additional benefit that a genotyped line can be used for phenotypic analysis multiple times, either to achieve replication or to study genotype-environment interactions. Our objective here is to carry out GWAS for drought tolerance in seedlings in order to identify the major determinants of natural variation for this trait in A. thaliana. This analysis will lead to the identification of many putative new components of the signalling network that are relevant in natural environments. These components will be further validated by the combinatorial use of crossings and transgenic approaches. The end-result will be better understanding of the molecular network that contributes to drought tolerance in Arabidopsis thaliana and in plants in general.