Cucumber seedlings were exposed to high temperatures to see how it affected their photosynthesis. The researchers found that the net photosynthetic rate and stomatal conductance decreased significantly under high temperature stress. Chlorophyll fluorescence parameters also decreased, while non-photochemical quenching increased. Seedlings treated at 35℃/20℃ showed some recovery after 2 days, but not fully. Those treated at 42℃/27℃ had more severe effects even after recovery.