A comparative study on the seed germination of selected species at the Gatersleben genebank to test the effect of freezing and rewarming on germinability

摘要

Research was carried out at the Gatersleben genebank to assess whether frequent freezing and rewarming has a negative effect on the germinability of seeds. Tests were carried out on four species Triticum aestivum and Secale cereale for cereals, Pisumsativum for legumes and Allium cepa for vegetables. After assessing the initial germinability of seeds, one lot of accessions of each species was kept as a control at -15 deg C while a second lot was frozen (-15 deg C) and then rewarmed (10 deg C) 20, 40, 60, 80, 100, 120, 140,160, 180 and 200 times. Throughout the experiment germination tests were conducted on both lots according to the international rules for seed testing. Only slight differences in germinability were observed for the four species tested even after 200 cycles of freezing-rewarming. These results show that it may no longer be necessary to split collections into base and active collections, thus facilitating genebank management.