Abstract

We examined seed germination and seedling root morphology of Crithmum maritimum, Dianthus rupicola, Primula palinuri and Eokochia saxicola. Specifically, we tested seed germination at five different solutions (distilled water; 20/80 v/v sea water/distilled water; 30/70 v/v; 50/50 v/v; sea water). Recovery of not germinated seeds when incubated in distilled water was assessed too. We also examined the seed germination at harvesting time, and four and 12 months later. Finally, we analysed the seedling root morphology at 8 and 12 days from seed imbibition. Salinity strongly inhibited germination in P. palinuri, while had minor effects on E. saxicola, C. maritimum and D. rupicola. Apart from E. saxicola, seeds remained viable for longer than a single reproductive cycle of the species. Only C. maritimum and D. rupicola have seedling roots capable of ensuring a strong adhesion to rock from the beginning of their development; seedling roots of P. palinuri and E. saxicola seem to do not have specific traits for anchoring the seedlings in the germination site. Our data revealed some weakness in P. palinuri and E. saxicola, two species threatened with extinction and included in European and international policy instruments. We found no such criticalities in the two other species.

摘要

我们研究了危地马拉（Crithmum maritimum），石竹（Dianthus rupicola），报春报（Primula palinuri）和横纹（Eokochia saxicola）的种子发芽和幼苗根系形态。具体而言，我们在五种不同的溶液（蒸馏水； 20/80 v / v海水/蒸馏水； 30/70 v / v； 50/50 v / v；海水）下测试了种子的萌发。还评估了在蒸馏水中孵育时未发芽种子的回收率。我们还在收获时以及四个月和十二个月后检查了种子的发芽情况。最后，我们分析了种子吸水后第8天和第12天的幼苗根系形态。在盐度强烈抑制发芽P. palinuri，而对微小的效应E.岩黄连，C. maritimum和D. rupicola。除沙门氏菌外，种子的存活时间还比该物种的单个繁殖周期更长。从生长的一开始，只有海地梭状芽孢杆菌和小球藻D. rupicola能够确保对岩石的牢固附着；P. palinuri和E. saxicola的幼苗根似乎没有将种子锚定在发芽部位的特定特征。我们的数据显示，P。palinuri和E. saxicola这两种濒临灭绝的物种已被弱化，并被纳入欧洲和国际政策工具。我们发现在另外两个物种中没有这样的关键性。