Plants maintain a dynamic balance between growth and defense , and optimize allocation of resources for survival under constant pathogen infections. However, the underlying molecular regulatory mechanisms, especially in response to biotrophic bacterial infection, remain elusive. Here, we demonstrate that DELLA proteins and EDS1, an essential resistance regulator, form a central module modulating plant growth–defense tradeoffs via direct interaction. When infected by Pst DC3000, EDS1 rapidly promotes salicylic acid (SA) biosynthesis and resistance-related gene expression to prime defense response, while pathogen infection stabilizes DELLA proteins RGA and RGL3 to restrict growth in a partially EDS1-dependent manner, which facilitates plants to develop resistance to pathogens. However, the increasingly accumulated DELLAs interact with EDS1 to suppress SA overproduction and excessive resistance response. Taken together, our findings reveal a DELLA–EDS1-mediated feedback regulatory loop by which plants maintain the subtle balance between growth and defense to avoid excessive growth or defense in response to constant biotrophic pathogen attack.

植物在生长和防御之间保持动态平衡，并在持续的病原体感染下优化资源分配以维持生存。但是，潜在的分子调控机制，尤其是对生物营养细菌感染的反应，仍然难以捉摸。在这里，我们证明了DELLA蛋白和EDS1是必需的抗性调节剂，通过直接相互作用形成了调节植物生长-防御权衡的核心模块。当被Pst感染时DC3000，EDS1迅速促进水杨酸（SA）的生物合成和抗性相关基因的表达，从而达到主要防御反应，而病原体感染稳定了DELLA蛋白RGA和RGL3，从而以部分EDS1依赖的方式限制了生长，从而促进了植物对病原体的抗性。但是，越来越多的DELLA与EDS1相互作用以抑制SA的过度生产和过度的电阻响应。综上所述，我们的发现揭示了一种由DELLA-EDS1介导的反馈调节回路，通过该回路，植物可在生长与防御之间保持微妙的平衡，从而避免对持续的生物营养性病原体攻击做出过度的生长或防御。