Photosynthetic characteristics of CO₂ enrichment in melon seedlings

Effects of CO₂ enrichment on photosynthetic characteristics of melon seedlings were studied in the experiment. The results indicated that different concentrations of CO₂ enrichment (800, 1000, 1200, 1400 μL/L) could obviously promote the maximum photosynthetic rates. Comparing with CK, the maximum photosynthetic rates increased by 9.59%, 70.52%, 80.64% and 131.21% respectively. Meanwhile, the transpiration rates descended respectively by12.16%, 27.18%, 37.34% and 54.65%. The difference between leaf and air temperature increased. Intercellular CO₂ concentration also increased by 12.04%～14.25%. With increasing CO₂ concentration, the light compensation point(LCP) decreased, but the light saturation point(LSP) increased. The optimal concentration of CO₂ enrichment in melon seedlings was about 1200 μL/L.