Regulation of Calcium on Photosystem of Tomato Leaves Under Sub-Low Night Temperature

摘要

In order to analyze the regulation function of calcium on photosystem of tomato leaves under sub-low night temperature, the effects of CaCl2 on the fluorescence of PS II and PS I under night chilling were studied. In order to select a appropriate concentration, the tomatoes ('Liaoyuanduoli') grown in greenhouse were pretreated with 0,30,60 and 90 mmol.L"'CaCl2 during the period of sub-low night temperature, and then chlorophyll fluorescence of PS II and PS I were measured by Dual PAM-100 (Heinz Walz, Effeltrich,Germany) ,the effect of sub-low night temperature on photosystem of tomato was discussed ,so does the regulation function of calcium. Results showed that the maximal photochemical efficiency of PS II (Fv/Fm), photochemical quantum yield of PS I (Y ( I )), was less than that of the control after night chilling. Fv/Fm in the tomato leaves pretreated with 30mmol.L"' CaCl2were much higher than that of control, while Y (ND) in the tomato leaves pretreated with 60 mmol.L"' CaCl2 were much higher than that of control under night chilling. The pretreatment of CaCl2 could improve photochemical activity of PS II and PSI of tomato leaves under sub-low night temperature. PS II and PSI have different sensitivity to CaCl2.