The role of seed dormancy and longevity in the annual and perennial life cycles

种子发芽的时间对于植物适应环境非常重要，并将影响到包括开花时间在内的所有后续发育阶段的时间。种子的休眠和寿命等性状决定了种子萌发的时间，并受种子成熟过程中环境条件的影响。目前对种子休眠和寿命的研究主要集中在拟南芥等一年生植物上，而对多年生植物的休眠和寿命研究甚少。该项目的目的是揭示一年生和多年生的生命策略如何影响种子的性状，如休眠和寿命。种子的休眠和寿命将在密切相关的芸苔科多年生和一年生植物和多年生模式植物阿拉比斯高山不同花期长度的资料中进行评分。此外，还将通过杂交多年生和一年生Erysimum capitatum进行种子性状的遗传剖析。基因DOG1和FLC影响种子和开花性状。它们在不同芸苔科植物种子和多年生性状中的作用将通过表达分析和转基因来确定。在自然条件下，通过将种子埋在土壤中两年以上的不同时间，研究所选物种的种子性状和种子基因的表达水平。该项目将为植物对环境的适应以及我们对生命史进化的理解提供新的见解。

The time when seeds germinate is important for the adaptation of plants to their environment and will influence the timing of all subsequent developmental phases including flowering time. Seed traits like dormancy and longevity determine the time of germination and are influenced by environmental conditions during seed maturation. Seed dormancy and longevity have mainly been studied in annual plants like Arabidopsis thaliana and little is known about these traits in perennial plants. The objective of this project is to reveal how the annual and perennial life strategies influence seed traits such as dormancy and longevity. Seed dormancy and longevity will be scored in sets of closely related perennial and annual Brassicaceae species and in accessions of the perennial model plant Arabis alpina with different lengths of flowering episodes. In addition, a genetic dissection of seed traits will be performed in relation to life strategies by crossing perennial and annual accessions of Erysimum capitatum.The genes DOG1 and FLC influence seed and flowering traits. Their role in seed and perennial traits of the different Brassicaceae species will be determined by expression analysis and transgenesis. Seed traits and expression levels of seed genes in the selected species will also be studied under natural conditions by burying seeds in the soil for various durations over two years.This project will give new insights in the adaptation of plants to their environment and in our understanding of life history evolution.