Flower preformation is a widespread phenomenon in perennial plants from temperate and cold regions. An advanced preformation status reduces the prefloration period and thus increases the chance to mature seeds in time. Despite the particular importance of this strategy for high-mountain plants, studies are rare. Here we investigated how the length of the growing season impacts floral development, and to what extent floral development is synchronized with reproductive phenophases in the arctic-alpine species Ranunculus glacialis L. The study was carried out in the alpine-nival ecotone in the European Central Alps at sites with different snowmelt dates. Individuals were sampled at regular intervals throughout the growing season, and shoot architecture and changes in floral structures were analysed in detail using different microscopic techniques. R. glacialis individuals consist of a cluster of independent ramets, comprising 3 sympodia each. Floral initiation terminates the vegetative growth of each sympodium 2–3 years before flowers become functional. A specific feature is that basal and distal leaves on a sympodium mature in different years. The date of snowmelt did not affect the speed of development but flower size and the number of lateral flowers within an inflorescence. Belowground floral preformation is closely linked to aboveground reproductive processes, however, continues below the snow in case winter conditions set in too early. The staggered preformation of architectural units creates a permanent belowground reserve pool of floral structures which might be advantageous in the climatically harsh and unpredictable high-mountain environment.

在来自温带和寒冷地区的多年生植物中，花的形成是普遍现象。先进的预成型状态缩短了花期，从而增加了及时成熟种子的机会。尽管此策略对高山植物特别重要，但很少进行研究。在这里，我们研究了生长期的长短如何影响花的发育，以及在何种程度上花的发育与北极高山物种毛an毛的生殖表相同步。L.这项研究是在欧洲中部阿尔卑斯山的高山-冬季过渡带中进行的，这些融雪日期不同。在整个生长季节中定期对个体进行采样，并使用不同的显微镜技术对枝条结构和花卉结构的变化进行详细分析。冰河鼠个体由一组独立的分株组成，每个分株有3个症状。在花开始起作用之前的2-3年，花的萌生终止了每种共生植物的营养生长。一个特殊的特征是，剑叶基部和远侧的叶在不同的年份成熟。融雪的日期并不影响发育速度，但会影响花的大小和花序中侧花的数量。地下花卉形成与地下生殖过程密切相关，但是，如果冬天条件过早，地下花卉将继续在雪下生长。建筑单元的交错式预制创造了一个永久的地下花卉结构储备池，这在气候恶劣和不可预测的高山环境中可能是有利的。