Wageningen UR Greenhouse Horticulture, 6700AP Wageningen, The Netherlands.
Ann Bot. 2011 Oct;108(6):1065-73. doi: 10.1093/aob/mcr221. Epub 2011 Aug 23.
Manipulation of plant structure can strongly affect light distribution in the canopy and photosynthesis. The aim of this paper is to find a plant ideotype for optimization of light absorption and canopy photosynthesis. Using a static functional structural plant model (FSPM), a range of different plant architectural characteristics was tested for two different seasons in order to find the optimal architecture with respect to light absorption and photosynthesis.
Simulations were performed with an FSPM of a greenhouse-grown tomato crop. Sensitivity analyses were carried out for leaf elevation angle, leaf phyllotaxis, leaflet angle, leaf shape, leaflet arrangement and internode length. From the results of this analysis two possible ideotypes were proposed. Four different vertical light distributions were also tested, while light absorption cumulated over the whole canopy was kept the same.
Photosynthesis was augmented by 6 % in winter and reduced by 7 % in summer, when light absorption in the top part of the canopy was increased by 25 %, while not changing light absorption of the canopy as a whole. The measured plant structure was already optimal with respect to leaf elevation angle, leaflet angle and leaflet arrangement for both light absorption and photosynthesis while phyllotaxis had no effect. Increasing the length : width ratio of leaves by 1·5 or increasing internode length from 7 cm to 12 cm led to an increase of 6-10 % for light absorption and photosynthesis.
At high light intensities (summer) deeper penetration of light in the canopy improves crop photosynthesis, but not at low light intensities (winter). In particular, internode length and leaf shape affect the vertical distribution of light in the canopy. A new plant ideotype with more spacious canopy architecture due to long internodes and long and narrow leaves led to an increase in crop photosynthesis of up to 10 %.
植物结构的调整会强烈影响冠层中的光分布和光合作用。本文旨在寻找一种植物理想形态，以优化光吸收和冠层光合作用。使用静态功能结构植物模型（FSPM），针对两个不同季节，测试了一系列不同的植物结构特征，以找到在光吸收和光合作用方面具有最佳结构的植物。
对温室种植的番茄作物的 FSPM 进行了模拟。对叶倾角、叶序、小叶角、叶形、小叶排列和节间长度进行了敏感性分析。根据该分析的结果，提出了两种可能的理想形态。还测试了四种不同的垂直光分布，同时保持整个冠层的光吸收总量不变。
在冬季，当冠层顶部的光吸收增加 25%而不改变整个冠层的光吸收时，光合作用增加了 6%，而在夏季则减少了 7%。就光吸收和光合作用而言，所测植物结构对于叶倾角、小叶角和小叶排列已经是最优的，而叶序没有影响。将叶片的长：宽比增加 1.5 倍或将节间长度从 7 厘米增加到 12 厘米，可使光吸收和光合作用增加 6-10%。
在高光强（夏季）下，冠层中光的更深穿透会提高作物的光合作用，但在低光强（冬季）下则不然。特别是，节间长度和叶形会影响冠层中的垂直光分布。由于长节间和长而窄的叶片，具有更宽敞冠层结构的新型植物理想形态可使作物光合作用增加高达 10%。
