首页分享滇西南山地球花报春种子形态与萌发沿海拔梯度的变异

滇西南山地球花报春种子形态与萌发沿海拔梯度的变异

来源：花匠小妙招时间：2025-11-11 20:41

摘要： 研究种子形态与萌发性状在山地生态系统的种内变异, 有助于揭示植物对环境变化的生态适应机制。该研究在滇西南高黎贡山沿2 180-3 451 m的海拔梯度采集13份球花报春(Primula denticulata)种子, 测定种子长、宽、宽/长、周长、面积、生物量、萌发最适温度(To)及最适温度下的萌发百分率(GP)、平均萌发时间(MGT)、萌发速率方差(VGR)和萌发同步性(GS), 并分析种子形态、萌发性状与海拔的关系。结果显示: (1)球花报春种子宽、面积和生物量随海拔上升显著增大, 但种子长、宽/长、周长随海拔变化不显著。(2) To随海拔上升显著降低; 最适温度下, MGT随海拔上升显著延长, GS则显著降低, 但GP、VGR与海拔的关系不显著。(3)海拔对种子宽、面积、生物量具有显著正效应, 形态性状变异引起MGT、GS沿海拔梯度变化。研究表明, 随着海拔上升, 球花报春种子生物量、宽度增加, 形态的改变导致其萌发时间延长、同步性降低, 暗示高海拔种子倾向于“多头下注”策略。

关键词: 功能性状, 高黎贡山, 海拔梯度, 生态适应

Abstract:

Aims This study aimed to investigate intraspecific variations in seed morphology and germination traits of Primula denticulataacross an elevational gradient in a mountain ecosystem, providing insights into ecological adaptations of plants to environmental changes.
Methods Seeds from 13 P. denticulatapopulations were collected along an elevational gradient of 2 180-3 451 m in the Gaoligong Mountains of southwestern Yunnan in China. We measured a variety of seed traits, including length, width, width-to-length ratio, perimeter, area, biomass, optimum germination temperature (To), germination percentage (GP), mean germination time (MGT), variance in germination rate (VGR) and germination synchronization (GS) at the optimum temperature. Then, we tested relationships between these seed traits and elevation.
Important findings Results showed that: (1) Seed width, area and biomass of P. denticulata increased significantly with increasing elevation, while seed length, width-to-length ratio and perimeter were not significantly associated with elevation. (2) To and GS decreased significantly with increasing elevation, and MGT at To increased significantly with increasing elevation. No significant relationships were found between GP and VGR and elevation. (3) Elevation had a significant positive effect on seed width, area, and biomass, and variations in these morphological traits contributed to longer MGT and reduced GS along the elevational gradient. These findings show that the width and biomass of P. denticulata seeds increased with elevation, leading to delayed germination and lower synchronization, suggesting that high-elevation populations tend to adopt a “long bet” germination strategy.

Key words: functional traits, Gaoligong Mountains, elevational gradient, ecological adaptation