Concentrative nitrogen allocation to sun-lit branches and the effects on whole-plant growth under heterogeneous light environments
Concentrative nitrogen allocation to sun-lit branches and the effects on whole-plant growth under heterogeneous light environments
复制标题
异质光环境下向阳枝的集中氮分配及其对全株生长的影响
DOI：
10.1007/s00442-012-2558-7
复制
发表时间：
2012
期刊：
影响因子：
2.7
通讯作者：
Masaki Tateno
中科院分区：
文献类型：
--
作者：
Daisuke Sugiura;Masaki Tateno
We investigated the nitrogen and carbohydrate allocation patterns of trees under heterogeneous light environments using saplings of the devil maple tree (Acer diabolicum) with Y-shaped branches. Different branch groups were created: all branches of a sapling exposed to full light (L-branches), all branches exposed to full shade (S-branches), and half of the branches of a sapling exposed to light (HL-branches) and the other half exposed to shade (HS-branches). Throughout the growth period, nitrogen was preferentially allocated to HL-branches, whereas nitrogen allocation to HS-branches was suppressed compared to L- and S-branches. HL-branches with the highest leaf nitrogen content (Narea) also had the highest rates of growth, and HS-branches with the lowest Nareahad the lowest observed growth rates. In addition, net nitrogen assimilation, estimated using a photosynthesis model, was strongly correlated with branch growth and whole-plant growth. In contrast, patterns of photosynthate allocation to branches and roots were not affected by the light conditions of the other branch. These observations suggest that tree canopies develop as a result of resource allocation patterns, where the growth of sun-lit branches is favoured over shaded branches, which leads to enhanced whole-plant growth in heterogeneous light environments. Our results indicate that whole-plant growth is enhanced by the resource allocation patterns created for saplings in heterogeneous light environments.
