Coordination of cyclic electron flow and alternative electron sinks adjusts photosynthetic regulation in maize under fluctuating light during combined heat and drought stress.

Coordination of cyclic electron flow and alternative electron sinks protects photosystem I in maize under fluctuating light during drought and heat stress, preventing photoinhibition.

• Why it matters: Understanding how maize adjusts its photosynthesis under combined environmental stresses is crucial for improving crop resilience amid climate change, yet the underlying mechanisms are not well understood.
• What they did: Researchers measured chlorophyll fluorescence, P700 redox state, and electrochromic shift signals in maize leaves exposed to fluctuating light under heat, drought, and combined stresses, focusing on electron flow and photoprotection.
• The result: They found that cyclic electron flow and alternative electron sinks were persistently stimulated under drought and compound stress, alleviating PSI limitations and preventing photoinhibition, thus revealing key regulatory strategies in maize.