Seed survival in ex situ genebanks

Plant genetic resources (PGR) play a major role for global food security. The most significant and widespread mean of conserving PGR is ex situ storage. Since the majority of genebank accessions globally are stored in the form of seed, seed longevity is of particular importance for crop germplasm preservation. Research was initiated for a range of crops stored in the German genebank over decades. Variation between crop species was detected. However, there is also intraspecific variation within genebank collections. It was concluded that the differences in germination after long term storage are genetically based. Therefore, genetic analyses of seed longevity were initiated. Genetic mapping was performed for barley, wheat, oilseed rape and tobacco.

In addition, mass spectrometry based untargeted metabolite profiling experiments were performed, in order to detect biochemical changes coinciding with loss in seed germination. The lipidomic composition of a wheat panel was investigated using high-resolution liquid chromatography-mass spectrometry (LC-MS). A high proportion of tentative oxidized lipids was detected, suggesting lipid oxidation as the causal trigger for membrane degradation.