The functions of phenotypic plasticity in plant-plant interactions and canopy productivity

在所有农业系统和育种者的田地中，生长的植物通过调整其形态和生理特征，与邻近植物创造的小气候不断相互作用。这些调节的能力，即表型可塑性，对于资源捕获和冠层中单个植物的适合性是必不可少的。然而，表型可塑性会促进植物间的资源争夺，从而降低冠层总生产力。直到今天，将这些植物-植物相互作用对植物和树冠性能的影响定量地剖析成生理上可解释的参数的实验方法令人惊讶地稀少。我们建议利用表型组学和3D-D建模方法的最新进展来理解植物-植物相互作用的表型可塑性策略及其对冠层生产力的功能影响。我们计划利用228个冬小麦品种来检验7个主要假说，这些假说涉及叶、茎和根性状的塑料驯化对资源捕获、个体基因型在异质冠层中的适合度和冠层总生产力的影响。全基因组关联研究将被用来确定负责对环境波动的可塑性或不变反应的基因组区域。将使用机械功能结构植物模型(FSPM)将叶、茎和根的动态驯化与冠层内的小气候相结合，并将构建大型虚拟实验，以确定在各种环境情景下最小化植物-植物竞争和最大化冠层生产力的理想策略。此外，我们提出了一个理论框架(Tf)来预测生长在同质冠层中的一个基因的表现，通过修正该基因在异质冠层中的表现与它的竞争力。预计拟议的FSPM和TF将分别为农业系统(例如品种混合)的设计和由于育种者田地中植物与植物之间的竞争而产生的选择偏差提供见解。

In all agriculture systems and breeders’ fields, growing plants interact continuously with the microclimate created by their neighboring plants by adjusting their morphological and physiological characteristics. The ability of these adjustments, namely phenotypic plasticity, is essential for resource capture and fitness of individual plant in the canopy. However, phenotypic plasticity can favor competition of resource capture between plants and penalize total canopy productivity. Experimental methods which quantitatively dissect the effects of these plant-plant interactions on plant and canopy performance into physiologically interpretable parameters are astonishingly scarce until today. We propose to use recent advances in phenomics and 3D-dmodelling approach to understand the strategies of phenotypic plasticity for plant-plant interactions and their functional effects on canopy productivity. We plan to use 228 winter wheat genotypes to test seven main hypotheses related to the effects of plastic acclimations of leaf, stem and root traits on the resource capture, fitness of individual genotype in a heterogeneous canopy and the total canopy productivity. Genome-wide association study will be used to identify the genomic regions responsible for the plastic or invariant response of a trait to the environmental fluctuations. A mechanistic functional-structural plant model (FSPM) will be used to integrate the dynamic acclimation of leaf, stem and root to the microclimate in a canopy will be constructed to conduct large-scale virtual experiments, which allow identification of the ideal strategies for minimizing plant-plant competition and maximizing canopy productivity under various environmental scenarios. Furthermore, we propose a theoretical framework (TF) to predict the performance of a genotype grown in a homogenous canopy by correcting the performance of this genotype under heterogeneous canopy with its competitiveness. The proposed FSPM and TF are expected to provide insights into the design of agricultural systems (e.g. varietal mixture) and the selection bias due to plant-plant competition in the breeders´ fields, respectively.