X射线辐射对小麦幼苗生长及一些抗氧化酶活性的影响

萌发４８ｈ的小麦幼苗用Ｘ射线处理，高剂量Ｘ射线（８Ｇｙ、１４Ｇｙ）可导致小麦幼苗生长受抑制，鲜重降低，在Ｘ射线照射后第２ｄ和第４ｄ测定幼苗内蛋白质含量、抗坏血酸过氧化物酶（ＡＳＡ－ＰＯＤ）、谷胱甘肽过氧化酶（ＧＳＨ－Ｐｘ）及谷胱甘肽巯基转移酶（ＧＳＨ－Ｔｓ）活性的变化。结果可知：Ｘ射线可引起小麦幼苗内蛋白质含量的下降，１４ＧｙＸ射线照射的样品低于８Ｇｙ照射的，照射后第４ｄ的蛋白质含量高于照射后第２ｄ的，说明Ｘ射线引起的损伤可随照射后的培养而有所恢复；高剂量Ｘ射线可引起小麦幼苗内一些抗氧化酶活性的升高，且随照射剂量的增加酶活性的升高也越明显，在照射后第４ｄ幼苗的ＡＳＡ－ＰＯＤ和ＧＳＨ－Ｐｘ活性高于照射后第２ｄ的值，ＧＳＨ－Ｔｓ活性略有下降。而低剂量（２Ｇｙ）照射与对照相比，上述指标变化不大，说明Ｘ射线处理后可通过诱导这些抗氧化酶活性的升高起到减轻伤害的作用。

EFFECT OF X IRRADIATION ON THE GROWTH AND SOME ANTIOXIDASE ACTIVITY IN WHEAT SEEDLINGS

Wheat seedlings of 48h after germination were irradiated with various dosage of X rays High dosage X irradiation, 8 Gy and 14 Gy can inhibited the growth, decrease the freshness weight of wheat seedlings The height and weight of wheat seedlings decreased with the development of X irradiation of dosage The concentration of protein and activity of some antioxidases include ascorbic acid peroxidase (ASA POD), glutathione peroxidase (GSH Px) and glutathione transferase (GSH Ts) were observed on 2nd and 4th day after irradiation The concentration of protein in wheat seedlings decreases with the development of X irradiation of dosage The concentration of protein on 4th day was higher than that on 2nd day showed that the damage of wheat seedlings induced by X irradiation was resumed during the culture process X irradiation can increase activity of ASA POD, GSH Px and GSH Ts of wheat seedlings, and the increase rate of 14Gy X irradiation was higher than that of 8Gy The activity of ASA POD and GSH Px increased during the culture process and the activity of GSH Ts decreased That's show that wheat seedlings can increase the activity of antioxidases to resist the damage induced by high dosage X irradiation The results of low dosage X irradiation, 2Gy is similar as the control