Global warming may pose a serious threat to seed germination and establishment in alpine ecosystems, given that temperature is a primary factor in stimulating seed germination and regulating changes in seed dormancy. However, to date, little is known about the relative importance of temperatures experienced by parents versus by the seeds (after dispersal). In this study, we tested the effects of warming at different stages on germination success and timing in the Australian alpine herb Wahlenbergia ceracea. To decouple the effect of parental warming from that of offspring warming, we raised parental plants (in both outcrossed and selfed lines) in both current (benign, cool) and future (warm) temperature conditions, and then sowed the seeds they produced back in either current or future conditions. We quantified (1) the effects of parental and/or offspring warming on (i) the percentage of germination and (ii) the season of germination (i.e. effects on dormancy); (2) whether the season of germination affected seedling growth; and (3) the effects of inbreeding and its interaction with temperature. We found that the percentage of germination decreased slightly with parental warming, but increased greatly with offspring warming. Parental warming also increased the fraction of dormant seeds, indicating a shift from predominately autumn to spring emergence. Spring-emerged seedlings grew slower than autumn-emerged seedlings, but the growth rate of spring-emerged seedlings were not detrimentally affected by warm offspring temperatures. In this facultatively autogamous species, inbreeding magnified the negative effects of both parental and offspring warming. Our results illustrate the value of tests of the effects of warming across generations and on multiple life stages for improving our understanding of the ecological processes behind plant germination and establishment, and of plant responses to climate warming.

鉴于温度是刺激种子发芽和调节种子休眠变化的主要因素，全球变暖可能对高山生态系统中的种子发芽和定植构成严重威胁。然而，迄今为止，关于父母经历的温度与种子经历的温度（分散后）的相对重要性知之甚少。在这项研究中，我们测试了澳大利亚高山草药Wahlenbergia ceracea在不同阶段变暖对发芽成功和时机的影响。。为了将亲代变暖的影响与后代变暖的影响分开，我们在当前（良性，凉性）和未来（温暖）温度条件下（在异交和自交系中）育成了亲本植物，然后将它们产生的种子播种回去。当前或将来的条件。我们量化（1）父母和/或后代变暖对（i）发芽百分比和（ii）发芽季节（即对休眠的影响）的影响；（2）发芽季节是否影响幼苗生长；（3）近交的影响及其与温度的相互作用。我们发现发芽的百分比随着父母的变暖而略有下降，但是随着后代的变暖而大大增加。父母的变暖也增加了休眠种子的比例，表明从主要的秋季到春季出现了转变。春季出苗的生长速度比秋季出苗的生长慢，但是春季出苗的生长速度不受后代温度升高的不利影响。在这种兼性的自交配种中，近交会放大父母和后代变暖的负面影响。我们的结果说明了世代之间和多个生命阶段变暖的影响测试的价值，对于增进我们对植物发芽和定殖背后的生态过程以及植物对气候变暖的响应的理解的价值。近亲繁殖放大了父母和后代变暖的负面影响。我们的结果说明了世代之间和多个生命阶段变暖的影响测试的价值，对于增进我们对植物发芽和定殖背后的生态过程以及植物对气候变暖的响应的理解的价值。近亲繁殖放大了父母和后代变暖的负面影响。我们的结果说明了世代之间和多个生命阶段变暖的影响测试的价值，对于增进我们对植物发芽和定殖背后的生态过程以及植物对气候变暖的响应的理解的价值。