Wang Pengrui, Zhou Chiyu, Yang Boning, Li Jiangfei, Xu Yulan, Cai Nianhui
The Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China Ministry of Education, Southwest Forestry University, Kunming 650233, China.
Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Southwest China, Kunming 650224, China.
Plants (Basel). 2025 Jul 22;14(15):2251. doi: 10.3390/plants14152251.
, a native tree species in southwest China, is shading-tolerant and ecologically significant. Light has a critical impact on plant physiology, and decapitation improves canopy light penetration and utilization efficiency. The study of allometric relationships is well-known in forestry, forest ecology, and related fields. Under control (full daylight exposure, 0% shading), L1 (partial shading, 25% shading), L2 (medium shading, 50% shading), and L3 (serious shading, 75% shading) levels, this study used the decapitation method. The results confirmed the effectiveness of decapitation in annual and showed that the main stem maintained isometric growth in all shading treatments, accounting for 26.8% of the individual plant biomass, and exhibited dominance in biomass allocation and high shading sensitivity. These results also showed that lateral roots exhibited a substantial biomass proportion of 12.8% and maintained more than 0.5 of higher plasticity indices across most treatments. Moreover, the lateral root exhibited both the lowest slope in 0.5817 and the highest significance ( = 0.023), transitioning from isometric to allometric growth under L1 shading treatment. Importantly, there was a positive correlation between the biomass allocation of an individual plant and that of all components of annual . In addition, the synchronized allocation between main roots and lateral branches, as well as between main stems and lateral roots, suggested functional integration between corresponding belowground and aboveground structures to maintain balanced resource acquisition and architectural stability. At the same time, it has been proved that the growth of lateral roots can be accelerated through decapitation. Important scientific implications for annual management were derived from these shading experiments on allometric growth.
[物种名称]是中国西南地区的本土树种，耐阴且具有重要的生态意义。光照对植物生理有至关重要的影响，去顶处理可提高树冠的光穿透率和利用效率。异速生长关系的研究在林业、森林生态学及相关领域广为人知。本研究采用去顶方法，设置了对照（全光照，0%遮荫）、L1（部分遮荫，25%遮荫）、L2（中度遮荫，50%遮荫）和L3（重度遮荫，75%遮荫）水平。结果证实了去顶处理在[物种名称]一年生植株中的有效性，表明在所有遮荫处理下主茎保持等速生长，占单株生物量的26.8%，在生物量分配中占主导地位且对遮荫敏感。这些结果还表明，侧根生物量比例达12.8%，在大多数处理中保持大于0.5的较高可塑性指数。此外，侧根在L1遮荫处理下斜率最低，为0.5817，显著性最高（P = 0.023），从等速生长转变为异速生长。重要的是，单株生物量分配与[物种名称]一年生植株各组分生物量分配之间存在正相关。此外，主根与侧枝之间以及主茎与侧根之间的同步分配表明，相应的地下和地上结构之间存在功能整合，以维持资源获取平衡和结构稳定性。同时，已证明去顶处理可加速侧根生长。这些关于异速生长的遮荫实验对[物种名称]一年生植株管理具有重要的科学意义。
