The study looked at how adding spermidine to cucumber plants affected their growth and photosynthesis when they were stressed by salt. Salt stress made the plants grow slower and reduced their ability to photosynthesize, but spermidine helped improve their growth and photosynthesis by increasing chlorophyll levels and enhancing photosynthetic processes. Spermidine mainly helped by improving the plants' ability to take in carbon dioxide through their stomata. Treating the leaves with spermidine was more effective than treating the roots.