Foliar carbon dots improve drought tolerance in soybean through genotype-dependent hydraulic and metabolic pathways.

Foliar carbon dots improve drought tolerance in soybean through genotype-dependent hydraulic and metabolic pathways, with wild and cultivated soybeans responding differently.

• Why it matters: Understanding how foliar carbon dots (CDs) alleviate drought stress is crucial for optimizing their use in soybean cultivation, yet the specific pathways and genotype differences remain unclear.
• What they did: The study applied 50 mg L-1 CDs at key growth stages to wild (Y15) and cultivated (Zhonghuang 13) soybeans under full and deficit irrigation, measuring photosynthesis, hydraulic properties, hormone levels, oxidative stress, and osmotic substances.
• The result: CDs increased predawn water potential by 27.9% and K leaf by 35.4%, with wild soybean showing improved A n via hydraulic pathways, while cultivated soybean enhanced g s and A n through osmotic adjustment, indicating genotype-dependent drought mitigation mechanisms.