Abstract:

In order to investigate the regulating mechanism of calcium on tomato low light tolerance, leaves of one tomato low light tolerance strain W (Lycopersicon esculentum Mill) were used to study the changes of protective enzymes activities and soluble protein content in leaves after the tomato were treated by calcium or calcium and IAA under the 50% nature light intensity (identical radiant flux of 556.8 to 656.6 μmol·m^-2·s^-1). The results showed that 27 mmol·L^-1 CaCl₂ treatment could significantly decrease MDA content, increase the activities of SOD,CAT,and POD, promote the content of soluble protein in the leaves of tomato under low light stress reach the control level under 100% nature light intensity; auxin could promote the effect of Ca²⁺ further. These results indicated that the effects of calcium on the activities of protective enzymes and the content of soluble protein in the leaves of tomato under low light stress maybe one of the important reasons for that calcium could increased low light tolerance of tomato and prevented low light damage to the plant.

Key words: tomato, calcium, low light stress, activities of cell defense enzymes, soluble protein