State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China.
Department of Biology, University of Kentucky, Lexington, KY, 40506, USA.
Sci Rep. 2017 Oct 24;7(1):13893. doi: 10.1038/s41598-017-14267-2.
Knowledge of the germination behavior of different populations of a species can be useful in the selection of appropriate seed sources for restoration. The aim of this study was to test the effect of seed population, collection year, after-ripening and incubation conditions on seed dormancy and germination of Stipa bungeana, a perennial grass used for revegetation of degraded grasslands on the Loess Plateau, China. Fresh S. bungeana seeds were collected from eight locally-adapted populations in 2015 and 2016. Dormancy and germination characteristics of fresh and 6-month-old dry-stored seeds were determined by incubating them over a range of alternating temperature regimes in light. Effect of water stress on germination was tested for fresh and 6-month-old dry-stored seeds. Seed dormancy and germination of S. bungeana differed with population and collection year. Six months of dry storage broke seed dormancy, broadened the temperature range for germination and increased among-population differences in germination percentage. The rank order of germination was not consistent in all germination tests, and it varied among populations. Thus, studies on comparing seed dormancy and germination among populations must consider year of collection, seed dormancy states and germination test conditions when selecting seeds for grassland restoration and management.
了解一个物种不同种群的萌发行为对于选择适当的种子资源进行恢复可能是有用的。本研究旨在测试种子种群、采集年份、后熟和培养条件对中国黄土高原退化草地植被恢复用多年生草本植物芨芨草种子休眠和萌发的影响。2015 年和 2016 年，从 8 个当地适应的种群中采集了新鲜的芨芨草种子。通过在光照下在一系列交替温度条件下孵育新鲜和 6 个月干贮藏的种子来确定休眠和萌发特性。对新鲜和 6 个月干贮藏的种子进行水分胁迫对萌发的影响测试。芨芨草的种子休眠和萌发随种群和采集年份而异。6 个月的干贮藏打破了种子休眠，扩大了萌发的温度范围，并增加了种群间萌发百分比的差异。在所有萌发试验中，萌发的等级顺序并不一致，而且在种群之间也存在差异。因此，在选择用于草地恢复和管理的种子时，比较种群间种子休眠和萌发的研究必须考虑采集年份、种子休眠状态和萌发试验条件。
