Bertel Clara, Hacker Jürgen, Neuner Gilbert
Department of Botany, University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria.
Hechenbichler GmbH, Cusanusweg 7-9, 6020 Innsbruck, Austria.
Plants (Basel). 2021 May 20;10(5):1031. doi: 10.3390/plants10051031.
In the temperate zone of Europe, plants flowering in early spring or at high elevation risk that their reproductive organs are harmed by episodic frosts. Focusing on flowers of two mountain and three early-flowering colline to montane distributed species, vulnerability to ice formation and ice management strategies using infrared video thermography were investigated. Three species had ice susceptible flowers and structural ice barriers, between the vegetative and reproductive organs, that prevent ice entrance from the frozen stems. Structural ice barriers as found in and sp. have not yet been described for herbaceous species that of corroborates findings for woody species. Flowers of and were ice tolerant. For all herbs, it became clear that the soil acts as a thermal insulator for frost susceptible below ground organs and as a thermal barrier against the spread of ice between individual flowers and leaves. Both ice barrier types presumably promote that the reproductive organs can remain supercooled, and can at least for a certain time-period escape from effects of ice formation. Both effects of ice barriers appear significant in the habitat of the tested species, where episodic freezing events potentially curtail the reproductive success.
在欧洲温带地区，早春开花或在高海拔地区开花的植物面临着其生殖器官受偶发霜冻伤害的风险。以两种山地植物和三种从低地到山地分布的早花植物的花朵为研究对象，利用红外视频热成像技术研究了它们对结冰的脆弱性及结冰应对策略。三种植物的花朵易结冰，且在营养器官和生殖器官之间存在结构性冰障，可防止冰从冻茎进入。在[具体物种1]和[具体物种2]中发现的结构性冰障，草本植物中尚未有相关描述，而[具体物种3]的情况则证实了木本植物的相关研究结果。[具体物种4]和[具体物种5]的花朵具有耐冰性。对于所有草本植物而言，很明显土壤对易受霜冻影响的地下器官起到了隔热作用，并且作为一道热障阻止冰在单个花朵和叶片之间扩散。这两种冰障类型可能都有助于生殖器官保持过冷状态，并且至少在一定时间段内免受结冰影响。在受试物种的栖息地，偶发的冰冻事件可能会降低繁殖成功率，冰障的这两种作用似乎都很重要。
