Abstract:

In order to study the effect of ⁶⁰Co-γ ray radiation on the growth of alfalfa seedlings and the activity of two antioxidant enzymes, the experiment was carried out with the dry seeds of ‘Longmu 806’ as the material. The seeds were treated with different doses of ⁶⁰Co-γ ray radiation (600,900,1 200,1 500 and 1 800 Gy).The effects of ⁶⁰Co-γ ray radiation on the germination rate of seeds, survival rate of seedling, seedling height, growth index and peroxidase and catalase activities in leaves were studied. The results showed that the germination rate and seedling survival rate of Alfalfa dry seeds after ⁶⁰Co-γ ray radiation presented a downward trend with the increase of radiation dose, and the seedling rate was 0 when the radiation dose was 1 800 Gy. With the increase of radiation dosage, the length of the seedlings and the length of the stems increased first and then decreased, the length of the main roots , the fresh weight, dry weight and moisture content of the seedlings all showed a decreasing trend. The catalase activity and peroxidase activity of the seedling leaves and roots increased first and then decreased with the increase of radiation dosage. When the radiation dose was 900 Gy, the activity of the two enzymes had the maximum accumulation.

Key words: Alfalfa seed, ⁶⁰Co-&gamma, radiation, Seedling growth, Antioxidant enzyme activity

摘要：

为研究⁶⁰Co-γ射线辐射对苜蓿幼苗生长和两种抗氧化酶活性的影响，试验以‘龙牧806’苜蓿干种子为材料，对其进行⁶⁰Co-γ不同辐射剂量（600，900，1 200，1 500和1 800 Gy）处理，研究⁶⁰Co-γ射线辐射对苜蓿种子出苗率、成苗率、幼苗株高等生长指标和叶片的过氧化物、过氧化氢酶活性的影响。结果表明：经过⁶⁰Co-γ射线辐射过后的苜蓿干种子出苗率和成苗率均表现为随着辐射剂量的升高呈现出下降的趋势，并且当辐射剂量为1 800 Gy时，幼苗的成苗率为0。其幼苗的长度和地上茎长度呈先增加后下降的变化趋势，主根长度呈现下降的变化趋势，幼苗的鲜重、干重和含水量均呈下降的变化趋势。幼苗的叶片和根的过氧化氢酶活性、过氧化物酶活性均随辐射剂量的增加表现出先上升后下降的变化趋势，辐射剂量为900 Gy时两种酶活性均有最大积累。

关键词: 苜蓿种子, ⁶⁰Co-&gamma, 辐射, 幼苗生长, 抗氧化酶活性