Plant community-level studies on seed dormancy traits are important to understand and determine the significance of seed dormancy in different ecosystems. Hence, we studied seed dormancy and other related seed biological traits of 42 selected tropical lowland rainforest tree species from Sri Lanka, aiming to address seed dormancy class(es) for a biodiverse tropical lowland wet zone forest community and the relationship between dormancy classes, forest strata and seed dispersal mechanisms. Seed germination, imbibition, embryo length:seed length ratio, embryo morphology and the effect of gibberrelic acid on seed germination were determined. Sixty-two percent of the species with T50 < 30 days were identified as having fast-germinating seeds and the remaining 38% with T50 > 30 possessed slow-germinating seeds. Seeds of 33 species had fully developed embryos, while nine species had underdeveloped embryos; three had morphological dormancy (MD) and six morphophysiological dormancy (MPD). Treatment with gibberellic acid revealed physiological dormancy (PD) in seeds of six species, and the response to manual scarification confirmed physical dormancy (PY) in seeds of Pericopsis moonina. The majority of tropical lowland rainforests had non-dormant (ND) species (62%), and 14.3, 14.3, 7 and 2.3% of the species had MPD, PD, MD, and PY, respectively. Non-dormancy decreased for taxa from the upper strata to the lower strata of the forest. ND seeds were dispersed during the rainy season. Thus, non-dormancy seems to be the most dominant germination behaviour among the tree species in the lowland rainforest of Sri Lanka with the class of dormancy related to forest strata and dispersal time.

关于种子休眠性状的植物群落水平研究对于理解和确定种子休眠在不同生态系统中的重要性非常重要。因此，我们研究了来自斯里兰卡的 42 种选定的热带低地雨林树种的种子休眠和其他相关种子生物学特性，旨在解决生物多样性热带低地湿地森林群落的种子休眠等级以及休眠等级与森林之间的关系。地层和种子传播机制。测定了种子萌发、吸水、胚长:种子长比、胚形态以及赤霉酸对种子萌发的影响。62% T 50 < 30 天的物种被确定为具有快速发芽的种子，其余 38% 的T 50> 30 拥有缓慢发芽的种子。33种种子发育完全胚，9种种子发育不全；三个具有形态休眠（MD）和六个形态生理休眠（MPD）。赤霉酸处理揭示了 6 种种子的生理休眠 (PD)，对人工划痕的反应证实了Pericopsis moonina种子的物理休眠 (PY). 大多数热带低地雨林有非休眠 (ND) 物种 (62%)，14.3、14.3、7 和 2.3% 的物种分别有 MPD、PD、MD 和 PY。从森林的上层到下层，分类群的非休眠减少。ND种子在雨季散播。因此，非休眠似乎是斯里兰卡低地雨林树种中最主要的发芽行为，休眠类别与森林层级和扩散时间有关。