凤眼莲超氧物歧化酶活性与抗寒性的关系

The Correlation Between Superoxide Dismutase Activity and Cold Resistance of Water Hyacinth

低温使凤眼莲叶内SOD活性降低,同时叶组织电解质外渗增加和TTG的还原力降低。用适量的联吡啶季胺盐(Paraquat)处理凤眼莲叶片,使超氧物歧化酶活性增强,则能减轻低温引起的伤害。试验提供了超氧物歧化酶与抗寒性有关的直接证据.

The correlation between superoxide dismu-tase (SOD) activity and cold hardiness ofwater hyacinth [Eichhornia crassipes (Mart.) Solms]was studied. SOD activity was promoted by pa-raquat treatment. The leaf electrolyte leakageand triphenyl tetrazolium chloride (TTC) redu-ction were examined to indicate the degree ofcold injury in the plant. The SOD activity in leaves of E .crassipesdecreased under low temperature. At the sametime, the leaf electrolyte leakage increased andTTC reduction decreased (Fig. 1). The SOD activity was increased by about45% by 30 μmol/L paraquat treatment. Theincreased SOD activity, however, was not stable.it gradually lowered to the control level within48 hours (Fig. 2). The increased SOD activitycould mitigate the cold injury. Both the increaseof electrolyte leakage and the decrease ofTTC reduction of paraquat treated plants weredelayed under low temperature (Fig. 3). The experimental result provides a directevidence for that the SOD activity is closely rela-ted to the cold hardiness of plants.