Tsogtsaikhan Tumenjargal, Yang Xuejun, Gao Ruiru, Liu Jiangrui, Tang Wenqiang, Liu Guofang, Ye Xuehua, Huang Zhenying
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
BMC Plant Biol. 2025 Jan 8;25(1):27. doi: 10.1186/s12870-024-06030-3.
Biomass allocation reflects functional tradeoffs among plant organs and thus represents life history strategies. However, little is known about the patterns and drivers of biomass allocation between reproductive and vegetative organs along large environmental gradients. Here, we examined how environmental gradients affect biomass and the allocation between reproductive and vegetative organs. We also tested whether the allocation patterns conform optimal or allometric partitioning theory.
We collected 22 Artemisia species along a large environmental gradient in China and measured reproductive (infructescences including seeds) and vegetative (leaves, stems and roots) mass for each plant. We then used standardized major axes regressions to quantify the relationships between reproductive and vegetative organs and linear mixed-effect models to examine the effect of environmental gradients (climate and soil) on biomass allocation patterns.
We found significant negative correlations between total biomass of Artemisia and the first principal component of climate, an axis that was negatively correlated with temperature and precipitation. Overall, there were significant isometric relationships between reproductive and vegetative mass. In addition, the ratio of reproductive to vegetative mass increased with the second principal component of climate (representing climate variability), but decreased with the second principal component of soil (representing bulk density and available water capacity). These patterns were consistent at the individual and interspecific levels, but were mixed at the intraspecific level.
Our findings of the plastic responses of biomass allocation to environmental gradients support the optimal partitioning theory (OPT). The isometric relationships between reproductive and vegetative organs indicate that plant growth and reproduction are intricately linked. Furthermore, the plasticity of biomass ratios of reproductive to vegetative organs to climate variability and soil physical properties suggests that the flexible allocation between growth and reproduction is crucial for successful adaptation to diverse habitats.
生物量分配反映了植物器官之间的功能权衡，因此代表了生活史策略。然而，对于沿大尺度环境梯度的生殖器官和营养器官之间生物量分配的模式和驱动因素，我们了解甚少。在此，我们研究了环境梯度如何影响生物量以及生殖器官和营养器官之间的分配。我们还测试了分配模式是否符合最优或异速生长分配理论。
我们在中国沿一个大尺度环境梯度收集了22种蒿属植物，并测量了每种植物的生殖（包括种子的果序）和营养（叶、茎和根）质量。然后，我们使用标准化主轴回归来量化生殖器官和营养器官之间的关系，并使用线性混合效应模型来研究环境梯度（气候和土壤）对生物量分配模式的影响。
我们发现蒿属植物的总生物量与气候的第一主成分之间存在显著的负相关，该主成分与温度和降水量呈负相关。总体而言，生殖质量和营养质量之间存在显著的等比关系。此外，生殖质量与营养质量的比值随气候的第二主成分（代表气候变异性）增加，但随土壤的第二主成分（代表容重和有效持水量）降低。这些模式在个体和种间水平上是一致的，但在种内水平上是混合的。
我们关于生物量分配对环境梯度的可塑性响应的研究结果支持最优分配理论（OPT）。生殖器官和营养器官之间的等比关系表明植物的生长和繁殖紧密相连。此外，生殖器官与营养器官的生物量比值对气候变异性和土壤物理性质的可塑性表明，生长和繁殖之间的灵活分配对于成功适应不同生境至关重要。
