Division of Grassland Science/Department of Crop Sciences, University of Göttingen, Von-Siebold-Str. 8, D-37075 Göttingen, Germany.
Centre of Biodiversity and Sustainable Land Use (CBL), University of Göttingen, Büsgenweg 1, D-37077 Göttingen, Germany.
Ann Bot. 2021 Jul 28;128(1):73-82. doi: 10.1093/aob/mcab040.
The drivers of white clover (Trifolium repens) architecture and productivity are still imperfectly understood. Our aim here was to investigate the impact of genetic background, neighbourhood and season on different architectural traits, clover and total biomass yield, as well as the relationship between those traits and yield.
We grew eight white clover populations in pure stands and in mixed stands with contrasting mixture partners. Over four consecutive regrowth periods within 1 year, we measured trait sizes and determined clover and total yield amounts.
The size of the architectural traits differed between populations and changed in response to neighbourhood and season. Population did not affect the sign or degree of those changes. Among the tested factors, season was by far the most important driver of white clover architecture, with the seasonal pattern notably differing between architectural traits. Clover and total yield were positively related to the architectural traits leaf area, petiole length, internode length and specific leaf area. Whereas the direction of the relationship was widely unaffected, its magnitude was clearly altered by neighbourhood and season.
Our results show that seasonal effects are the key for a deeper understanding of the architecture of white clover individuals and to improve the productivity of white clover communities.
白车轴草（Trifolium repens）的结构和生产力的驱动因素仍未被充分理解。我们的目的是研究遗传背景、邻接和季节对不同结构特征、白车轴草和总生物量产量的影响，以及这些特征与产量之间的关系。
我们在纯种植株和与对照组合有显著差异的混合种植中种植了八个白车轴草种群。在一年中的四个连续再生期内，我们测量了特征大小并确定了白车轴草和总产量。
结构特征的大小在种群之间存在差异，并响应邻接和季节而变化。种群并不影响这些变化的符号或程度。在所测试的因素中，季节是白车轴草结构的最重要驱动因素，季节性模式在不同的结构特征之间有显著差异。白车轴草和总生物量与结构特征的叶面积、叶柄长度、节间长度和比叶面积呈正相关。虽然关系的方向基本不受影响，但邻接和季节明显改变了关系的程度。
我们的结果表明，季节性影响是深入了解白车轴草个体结构和提高白车轴草群落生产力的关键。
