Abstract: Aims This study aimed to investigate intraspecific variation in seed morphology and germination traits of Primula denticulata across elevational gradients in a mountain ecosystem, providing insights into ecological adaptations of plants to environmental changes. Methods Seeds from 13 P.denticulata populations were collected along an elevational gradient of 2180–3451 m in the Gaoligong Mountains of southwestern Yunnan in China. Seed traits, including length, width, width-to-length ratio, perimeter, area, optimum germination temperature (To), germination percentage (GP), mean germination time (MGT), variance in germination rate (VGR) and germination synchronization (GS) at the optimum temperature of seeds, were assessed. Relationships between seed morphology and elevation, as well as between germination traits and elevation, were also determined. Important findings Results showed that: (1) Seed width, area and 100-seed mass of P.denticulata increased significantly with increasing elevation, while seed length, width-to-length ratio and perimeter showed no significant change. (2) To decreased significantly with increasing elevation. At To, the MGT increased significantly and GS decreased significantly with increasing elevation. However, GP and VGR were not markedly impacted by elevation. (3) Elevation had a significant positive effect on seed width, area, and 100-seed mass, with these morphological variations contributing to longer MGT and reduced GS along the elevational gradient. These findings indicate that the width and mass of P.denticulata seeds increased with elevation, leading to delayed germination and lower synchronization. This suggests that high-elevation populations tend to adopt a “long bet”germination strategy.

Key words: seed, functional traits, Gaoligong Mountains, elevational gradients, ecological adaptation