水稻幼苗超氧物歧化酶器官特异性的研究

A study on the Organ specifity of Superoxide Dismutase (SOD) in Rice Seedlings

以杂交水稻威优35、威优49及常规稻湘矮早9号为材料，研究了水稻叶片和根系超物氧岐化酶（SOD）的特性。结果表明：裟叶片和根系都具有三条SOD同工酶谱带，且在580nm处有三个明显的吸收峰；KCN抑制试验表明，三条谱带均为CU、Zn-SOD同工酶。对水稻SOD热稳定性测定表明，叶片和根系SOD对热都较稳定，60℃下恒温5分钟才明显失活；但叶片和根系SOD在最适反应温度、对外界逆境反应及活性分布上存在器官差异性。

Crude extract of superoxide dismutase(SOD)from both of the roots and the leaves of two hybrid rice(V35, V49)a convertional Variety (Xing, 9)seedlings were analyzed for their enzymic characteristics. The enzyme is present in the leaves and roots of the three species. on a fresh weight basis, leaves contain more enzyme than roots, whi1e on a soluble protein content in the crude extract, roots contain more enzyme than leaves. Electro phoresis iEdicated a total 3 of distinct forms of the enzyme in both of the leaves and roots, Scanning showed 3 distinet absorbance peaks at 580nm. aIl of the 3 isoenzyme activities were eliminated with cyanide treatment suggesting that they may be coprozine enzymes. Enzyme activities did not decrease sharply till 60 degC showing a heat stability,but the optimum temperature for the enzyme activitics of leaves was higher (35degC) than roots(30 degC). It’s also found that the enzyme activities of leaves were much more sensitivity to cold stress in the dark than that of roots.Thus some enzymic characteristics of SOD in rice seedlings exist organ specifity.