biostudies-literatureUnknown13Miao YSoil salinity severely inhibits leaf photosynthesis and limits agricultural production. Red to far-red light ratio (R/FR) affects leaf photosynthesis under salt stress, however, its regulation mechanism is still largely unknown. This study investigated the effects of different R/FR on plant growth, gas exchange parameters, photosynthetic electron transport, Calvin cycle and key gene expression under salt stress. Cucumber seedlings were exposed to four treatments including 0 mM NaCl and R/FR=7 (L7, control), 0 mM NaCl and R/FR=0.7 (L0.7), 80 mM NaCl and R/FR=7 (H7) and 80 mM NaCl and R/FR=0.7 (H0.7) for 9 days in an artificial climate chamber. The results showed that compared to L7 treatment, H7 treatment significantly reduced relative growth rate (RGR), CO₂ assimilation rate (<iFrontiers in plant science1053780https://www.ebi.ac.uk/biostudies/studies/S-EPMC9853560biostudies-literatureLow red to far-red light ratio promotes salt tolerance by improving leaf photosynthetic capacity in cucumber.PMC9853560Miao YBai LWang WGao XLi BfalseLow red to far-red light ratio promotes salt tolerance by improving leaf photosynthetic capacity in cucumber.Soil salinity severely inhibits leaf photosynthesis and limits agricultural production. Red to far-red light ratio (R/FR) affects leaf photosynthesis under salt stress, however, its regulation mechanism is still largely unknown. This study investigated the effects of different R/FR on plant growth, gas exchange parameters, photosynthetic electron transport, Calvin cycle and key gene expression under salt stress. Cucumber seedlings were exposed to four treatments including 0 mM NaCl and R/FR=7 (L7, control), 0 mM NaCl and R/FR=0.7 (L0.7), 80 mM NaCl and R/FR=7 (H7) and 80 mM NaCl and R/FR=0.7 (H0.7) for 9 days in an artificial climate chamber. The results showed that compared to L7 treatment, H7 treatment significantly reduced relative growth rate (RGR), CO₂ assimilation rate (<i2022-01-01T00:00:00Z20222025-04-22T09:07:57.957Z2025-04-05T22:50:55.753ZS-EPMC98535603668476910.3389/fpls.2022.1053780