抗感赤霉病小麦品种超氧化物歧化酶和过氧化氢酶的活性比较

COMPARISON FOR ACTIVITIES OF SUPEROXIED DISMUTASE AND CATALASE BETWEEN SCAB RESISTANT AND SUSCEPTIBLE WHEAT VARIETIES

用禾谷镰孢（ＦｕｓａｒｉｕｍｇｒａｍｉｎｅａｒｕｍＳｃｈｗ．）ＪＦ－１２菌株的子囊孢子悬浮液于抽穗期对望水白、扬麦４号和宁麦６号等不同程度抗赤霉病的小麦品种进行接种，比较了接种后不同时间穗组织中超氧化物歧化酶（ＳＯＤ）和过氧化氢酶（ＣＡＴ）的活力变化。结果表明：接种后抗病品种望水白ＳＯＤ活力下降，且一直处于较对照（未接种）低的水平。中抗品种扬麦４号和感病品种宁麦６号的ＳＯＤ活力初期略有下降，但很快明显升高并显著高于对照。而抗病品种接种后的ＣＡＴ活力则始终高于对照，感病品种则相反，一直低于对照。ＳＯＤ和ＣＡＴ均为活性氧代谢中重要的酶，可能在小麦的抗赤霉病过程中也有积极的作用，本文对此进行了讨论。

Three winter wheat varieties were inoculated at the heading stage by injecting into flowered with a droplet of 10 μl ascospore suspension of isolate JF 12 of Fusarium graminearum schw. Assay was made 0.5, 1, 2, 4, 8, 12 and 16 d after inoculation for the activities of superoxide dismutase (SOD) and catalase (CAT) in the sprike tissues. The results showed that in healthy spikes, activities of both SOD and CAT of resistant variety (Wangshuibai) are higher than that of moderately resistant (Yangmai NO. 4) and susceptible (Ningmai No.6) varieties. After inoculation, as compared with healthy spikes, Wangshuibai decreases in the activities of SOD by 4.1%～23.1% and increases in the activities of CAT by 0.6%～22.0%. The situation is opposite for Yangmai No. 4 and Ningmai No. 6, where the SOD activities are 9.8%～49.2% and 3.2%～31.2% higher, and CAT activities 4.4% ～41.6% and 0.9%～35.1% lower than that of healthy spikes. Possible involement of active oxygen free radicals, SOD and CAT in the plant pathogenisis is discussed.