Fire is an important ecological factor shaping plant strategies. Plants that are not able to survive fire and rely on seed reproduction may have seeds adapted for surviving heat shock or their germination may even be enhanced by heat or smoke. In order to find out whether such adaptations may be found in plants able to survive fire and resprout, we examined the germination of ten Vellozia species in response to heat shock and smoke. Seeds were collected in two community types differing in fire frequency: campos sujos (open savannas with frequent and hotter fires) and campos rupestres (montane grasslands on rocky outcrops, with less frequent and milder fires). We hypothesized that seeds of plants inhabiting campos sujos would be more tolerant to fire or will even be stimulated by heat shock or smoke in comparison with seeds of plants inhabiting campos rupestres. We confirmed our expectations only partly, as (i) seeds of all species survived heat shocks of 60 and 100°C for one minute and seeds of three species survived the temperature of 200°C, (ii) the smoke treatments increased germination by 20–40% in three species from both communities, and (iii) mortality after the hottest heat shock was greater in seeds of plants from campos rupestres than from campos sujos. Fire- and smoke-related germination strategies help populations of Vellozia species to cope with recurrent fires in fire-prone ecosystems.

中文翻译：

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热量和烟雾影响可燃重芽植物的萌发：塞拉多的 Vellozia 物种

火是塑造植物策略的重要生态因素。不能在火中存活并依靠种子繁殖的植物可能具有适应热休克的种子，或者它们的发芽甚至可以通过热量或烟雾增强。为了找出这种适应性是否可以在能够在火中存活并重新发芽的植物中发现，我们检查了 10 种 Vellozia 物种对热休克和烟雾的反应。在火灾频率不同的两种群落类型中收集种子：campos sujos（具有频繁和较热火灾的开阔稀树草原）和 campos rupestres（岩石露头上的山地草原，火灾频率较低且较温和）。我们假设，与居住在 campos rupestres 的植物种子相比，居住在 campos sujos 的植物种子更耐火，甚至会受到热休克或烟雾的刺激。我们仅部分证实了我们的预期，因为 (i) 所有物种的种子都能在 60 和 100°C 的热冲击下存活一分钟，三种物种的种子在 200°C 的温度下存活，(ii) 烟熏处理使发芽率提高了 20 –40% 来自两个社区的三个物种，并且 (iii) 最热热激后的死亡率在来自 Campos rupestres 的植物种子中高于来自 Campos sujos 的种子。与火灾和烟雾相关的萌发策略有助于 Vellozia 物种种群应对易发生火灾的生态系统中反复发生的火灾。因为 (i) 所有物种的种子都能在 60 和 100°C 的热冲击下存活一分钟，三个物种的种子在 200°C 的温度下存活，(ii) 烟熏处理使三个物种的发芽率提高了 20-40%两个社区，以及 (iii) 在最热的热休克之后，campos rupestres 植物种子的死亡率高于 campos sujos 植物种子。与火灾和烟雾相关的萌发策略有助于 Vellozia 物种种群应对易发生火灾的生态系统中反复发生的火灾。因为 (i) 所有物种的种子都能在 60 和 100°C 的热冲击下存活一分钟，三个物种的种子在 200°C 的温度下存活，(ii) 烟熏处理使三个物种的发芽率提高了 20-40%两个社区，以及 (iii) 在最热的热休克之后，campos rupestres 植物种子的死亡率高于 campos sujos 植物种子。与火灾和烟雾相关的萌发策略有助于 Vellozia 物种种群应对易发生火灾的生态系统中反复发生的火灾。