Pawłowski Tomasz A, Suszka Jan, Mucha Joanna, Zadworny Marcin, Alipour Shirin, Kurpisz Barbara, Chmielarz Paweł, Jagodziński Andrzej M, Chmura Daniel J
Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland.
Faculty of Forestry and Wood Technology, Poznan University of Life Sciences, Poznań, Poland.
Front Plant Sci. 2024 Jun 7;15:1355328. doi: 10.3389/fpls.2024.1355328. eCollection 2024.
Tree species' ability to persist within their current distribution ranges is determined by seed germination and seedling growth. Exploring variation in these traits in relation to climatic conditions helps to understand and predict tree population dynamics, and to support species management and conservation under future climate. We analyzed seeds and seedlings of 26 European beech populations from the northeastern boundary of the species range to test whether: 1) adaptation to climatic conditions is reflected in depth of dormancy and germination of seeds; 2) climatic characteristics of origin predictably affect seedling traits. The variation in seed dormancy and germination in a laboratory test, and seedling growth and morphology traits in a nursery common-garden test was examined. Populations originating from warmer and drier sites (mostly from the northern region), compared to those from the opposite end of climatic gradient, germinated later, with a lower success, and produced seedlings with shorter and tougher roots. They had deeper dormancy and poorer seed germination capacity, and are likely more vulnerable to environmental changes. The climatic conditions at the origin shape the intraspecific variation of seed germination and seedling traits, and may limit regeneration from seed and affect adaptation potential of beech to increasing temperatures and decreasing precipitation.
树种在其当前分布范围内的存续能力取决于种子萌发和幼苗生长。探究这些性状与气候条件相关的变异，有助于理解和预测树木种群动态，并为未来气候条件下的物种管理和保护提供支持。我们分析了来自该物种分布范围东北边界的26个欧洲山毛榉种群的种子和幼苗，以检验：1）对气候条件的适应性是否体现在种子休眠深度和萌发方面；2）起源地的气候特征是否可预测地影响幼苗性状。研究了实验室试验中种子休眠和萌发的变异，以及苗圃共同园试验中幼苗生长和形态性状的变异。与气候梯度另一端的种群相比，来自温暖干燥地区（主要是北部地区）的种群萌发较晚，成功率较低，且产生的幼苗根系更短更坚韧。它们具有更深的休眠和更差的种子萌发能力，可能更容易受到环境变化的影响。起源地的气候条件塑造了种子萌发和幼苗性状的种内变异，并可能限制种子更新，影响山毛榉对气温升高和降水减少的适应潜力。
