Abstract:
After firstly trained at 15℃ for 72 h in an illuminated incubator, the 3-year-old
Garcinia celebica seedlings were placed under 3, 6, or 9℃ for 36h for the experiment to observe the physiological responses of the plants to low temperatures. The contents of chlorophyll, soluble proteins and soluble sugars, as well as the activities of SOD and POD in the leaves of the seedlings were determined. It was found that the seedlings could restore their normal growth after an exposure to 6 or 9℃.Nevertheless, there were significant physiological alternations occurred to the plants due to the treatments. The contents of total chlorophyll, chlorophyll a, and chlorophyll b in the leaves were significantly lowered as compare to control. The soluble protein or soluble sugar content increased at 6℃ and 9℃, and peaked at 6℃. On the other hand, both of thesedecreased sharply at 3℃, and became lower than control.Meanwhile, the activities of SOD and POD in the leaves increased under 6℃ and 9℃ stresses. It was concluded that
G.celebica responded to the temperatureat 6℃ or 9℃ to tolerate the cold stressby accumulating soluble proteins and sugars regulating osmosisin the tissues, and at the same time, enhancing the activities of SOD and PODfor an improved adaptability to the environmental change.