Atmospheric CO₂ concentration [CO₂] has increased from 260 to 280 μmol mol⁻¹ (level during crop domestication up to the industrial revolution) to currently 400 and will reach 550 μmol mol⁻¹ by 2050. C3 crops are expected to benefit from elevated [CO₂] (e-CO₂) thanks to photosynthesis responsiveness to [CO₂] but this may require greater sink capacity. We review recent literature on crop e-CO₂ responses, related source-sink interactions, how abiotic stresses potentially interact, and prospects to improve e-CO₂ response via breeding or genetic engineering. Several lines of evidence suggest that e-CO₂ responsiveness is related either to sink intrinsic capacity or adaptive plasticity, for example, involving enhanced branching. Wild relatives and old cultivars mostly showed lower photosynthetic rates, less downward acclimation of photosynthesis to e-CO₂ and responded strongly to e-CO₂ due to greater phenotypic plasticity. While reverting to such archaic traits would be an inappropriate strategy for breeding, we argue that substantial enhancement of vegetative sink vigor, inflorescence size and/or number and root sinks will be necessary to fully benefit from e-CO₂. Potential ideotype features based on enhanced sinks are discussed. The generic ‘feast-famine’ sugar signaling pathway may be suited to engineer sink strength tissue-specifically and stage-specifically and help validate ideotype concepts. Finally, we argue that models better accounting for acclimation to e-CO₂ are needed to predict which trait combinations should be targeted by breeders for a CO₂-rich world.

大气中的CO ₂浓度[CO ₂ ]从260μmolmol ^-1（从农作物驯化到工业革命的水平）增加到目前的400，并且到2050年将达到550μmolmol ^-1。预计C3作物将从中受益由于对[CO ₂ ]的光合作用，[CO ₂ ]（e-CO ₂）的浓度升高，但这可能需要更大的吸收能力。我们回顾了有关作物e-CO ₂响应，相关的源库相互作用，非生物胁迫如何潜在相互作用以及通过育种或基因工程改善e-CO ₂响应的前景的最新文献。有几条证据表明，e-CO₂响应性与吸收固有容量或适应性可塑性有关，例如，涉及增强的分支。野生近缘种老品种大多表现出更低的光合速率，光合较小的向下驯化E-CO ₂和强烈的反应到E-CO ₂由于有较大的表型可塑性。虽然恢复到这种过时的性状对于繁殖是不合适的策略，但我们认为，要充分受益于e-CO _2，必须大幅提高植物的营养汇活力，花序大小和/或数量和根汇。。讨论了基于增强接收器的潜在意识型特征。通用的“ feast-famine”糖信号传导途径可能适合于特定于组织和特定于阶段设计吸收强度，并有助于验证表型概念。最后，我们认为需要模型来更好地解释对e-CO _2的适应，以预测育种者应该针对富含CO _2的世界定位哪些性状组合。