Seed dormancy in alpine species.
Seed dormancy in alpine species.
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DOI：
10.1016/j.flora.2011.05.001
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发表时间：
2011-10
期刊：
影响因子：
1.9
通讯作者：
Erschbamer B
中科院分区：
文献类型：
--
作者：
Schwienbacher E;Navarro-Cano JA;Neuner G;Erschbamer B
在高山植物中，种子休眠的各种机制的分类一直是相当可疑和有争议的。因此，我们调查了28种高山植物，以评估休眠的流行类型。种皮的胚型和水分不透性反映了种子潜在的休眠级别。为了确定实际的休眠级别和程度，我们进行了萌发试验，比较了未贮藏、冷干贮藏、冷湿贮藏和冷藏处理后种子的行为。我们还测试了一些物种对发芽的光照需求。用最终发芽率和平均发芽时间来表征种子的发芽行为。在此基础上，综合考虑不同处理方式的影响，构建了冬眠盛行类型的精细分类。在我们评估的28个物种中，只有两个物种的种子以非休眠为主。生理休眠在20种植物中普遍存在，其中深度生理休眠最为丰富，其次为非深度和中度生理休眠。将胚胎发育不良的4个种的种子归为形态生理休眠类。在两种植物中发现了一种不透水的种皮，没有额外的生理发芽障碍。我们将这些物种定义为具有生理休眠状态。除1个生理休眠种外，光照均能促进种子萌发而无需贮藏。在生理休眠的物种中，光反应是次要的。我们在以前发芽研究的背景下讨论了我们的新分类，并得出了对田间发芽时间的影响。
In alpine species the classification of the various mechanisms underlying seed dormancy has been rather questionable and controversial. Thus, we investigated 28 alpine species to evaluate the prevailing types of dormancy. Embryo type and water impermeability of seed coats gave an indication of the potential seed dormancy class. To ascertain the actual dormancy class and level, we performed germination experiments comparing the behavior of seeds without storage, after cold-dry storage, after cold-wet storage, and scarification. We also tested the light requirement for germination in some species. Germination behavior was characterized using the final germination percentage and the mean germination time. Considering the effects of the pretreatments, a refined classification of the prevailing dormancy types was constructed based on the results of our pretreatments. Only two out of the 28 species that we evaluated had predominantly non-dormant seeds. Physiological dormancy was prevalent in 20 species, with deep physiological dormancy being the most abundant, followed by non-deep and intermediate physiological dormancy. Seeds of four species with underdeveloped embryos were assigned to the morphophysiologial dormancy class. An impermeable seed coat was identified in two species, with no additional physiological germination block. We defined these species as having physical dormancy. Light promoted the germination of seeds without storage in all but one species with physiological dormancy. In species with physical dormancy, light responses were of minor importance. We discuss our new classification in the context of former germination studies and draw implications for the timing of germination in the field.