Southern European peninsulas have repeatedly played notable roles as refuges in the natural history of flora during periods of glaciation. Euonymus latifolius (Celastraceae) is a relict species from the last Würmian glaciation in the Iberian Peninsula. It still lives with isolated populations in favourable, cool mountainous microhabitats, being an extremely rare, critically endangered species. These Iberian populations are often high-priority targets for conservation due to their long-term persistence and unique evolutionary trajectory. Previously, it has not been feasible to promote significant programmes for reintroduction and/or population reinforcement of this singular plant species due to the great difficulties of conventional propagation. In this study, we analysed the effects of temperature, light and gibberellic acid (GA3) on the germination responses of E. latifolius to develop an effective protocol for seed germination as a main outcome. The results are coherent with the climatic temperature conditions recorded broadly in the Iberian Peninsula in the past and in the current refuge locations for the taxon. The germination responses of E. latifolius are compatible with those of seeds with intermediate physiological dormancy. In particular, the seeds required a 10-week warm period (20/7°C + 15/4°C) followed by 20 weeks of cold period (5 + 1.5°C) to break dormancy and achieve germination values over 90%. GA3 also promoted germination (80%). Therefore, we developed the first effective protocol for promoting E. latifolius seed germination and, thus, sexual propagation, to facilitate urgent ex situ actions in the current climate change context.

南欧半岛在冰川时期的植物群自然历史中多次扮演着重要的避难所角色。大叶卫矛（卫矛科）是伊比利亚半岛末次乌尔米亚冰期的孑遗物种。它仍然与孤立的种群一起生活在有利、凉爽的山区微生境中，是一种极其稀有、极度濒危的物种。由于其长期存在和独特的进化轨迹，这些伊比利亚种群通常是重点保护目标。此前，由于传统繁殖的巨大困难，推动这种单一植物物种的重新引入和/或种群强化的重大计划并不可行。在本研究中，我们分析了温度、光照和赤霉酸（GA 3 ）对阔叶桉发芽反应的影响。主要成果是制定有效的种子发芽方案。结果与伊比利亚半岛过去和目前该类群避难地点广泛记录的气候温度条件一致。E. latifolius的发芽反应与具有中间生理休眠的种子的发芽反应一致。特别是，种子需要10周的温暖期（20/7°C + 15/4°C），然后是20周的寒冷期（5 + 1.5°C）才能打破休眠并达到90%以上的发芽率。GA 3还促进发芽（80%）。因此，我们开发了第一个有效的方案来促进E. latifolius种子发芽，从而促进有性繁殖，以促进紧急异地当前气候变化背景下的行动。