硒锌和富啡酸配施对紫花苜蓿叶片抗氧化酶活性及产量的影响

在氮磷钾供应充分情况下，采用大田小区试验方法，通过播前基施硒（Se）、锌（Zn）微肥和腐殖酸（富啡酸，fulvic acid，FA），设对照（CK，不施肥）、施氮磷钾（NPK）、增施富啡酸（NPK+FA）、增施锌、硒微肥（NPK+Zn+Se）、增施富啡酸和锌、硒微肥（NPK+FA+Zn+Se）等5个不同施肥处理，在严重缺硒和锌石灰性土壤中，研究了硒锌和富啡酸配施对紫花苜蓿叶片内过氧化物酶（POD）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）等抗氧化酶活性、游离脯氨酸（Pro）及丙二醛（MDA）和干草产量的影响。结果表明：两茬中叶片过氧化物酶（POD）活性均以NPK+FA处理最高，其次是NPK+FA+Zn+Se处理，说明富啡酸（FA）比微肥（Se+Zn）更能有效提高紫花苜蓿叶片过氧化物酶活性，而硒锌对其活性影响不显著；硒锌与富啡酸配施可显著提高紫花苜蓿叶片内游离脯氨酸（Pro）含量、过氧化氢酶（CAT）及超氧化物歧化酶（SOD）活性，从而显著提高紫花苜蓿抗氧化能力；但各施肥处理对丙二醛（MDA）无显著影响。施肥可显著提高紫花苜蓿产量，施用富啡酸比硒锌微肥的增产效果更明显，且硒锌与富啡酸配施效果最好。因此，在氮磷钾供应充足条件下，适量硒锌微肥或富啡酸均能显著提高紫花苜蓿的抗氧化能力及提高紫花苜蓿产量，且微肥和富啡酸配施效果最好。

Effect of Se-Zn and Fulvic Acid Combined Application on the Antioxidant Enzyme Activity of Alfalfa Leaves and Hay Yield

Under the condition of sufficient supply of nitrogen,phosphorus and potassium fertilizer,a field plot experiment was conducted to study the effects of selenium (Se),zinc (Zn) micro-fertilizer and fulvic acid (FA) before sowing. The experiment including CK (no fertilization),NPK,NPK+FA,NPK+Zn+Se and NPK+FA+Zn+Se five different fertilization treatments. In the severe selenium and zinc deficient soils,effects of the combination ofSe,Zn and FA application on superoxide dismutase (SOD) activity,peroxide enzyme (POD) activity,catalase (CAT) activity,free proline (Pro) and malondialdehyde (MDA) content in alfalfa leaves and hay yield of alfalfa in calcareous Chao soil were studied. The results showed that the peroxidase (POD) activity in leaves of two cuts was the highest in NPK+FA treatment,followed by NPK+FA+Zn+Se treatment,it could suggest that the FA more than Se-Zn micro-element fertilizer could effectively improve POD activity of alfalfa leaves,but Se-Zn micro-element fertilizer had no significant effects on the POD activity. Se-Zn and FA combined application could effectively increase the stress resistance of alfalfa by improving the free proline (Pro) content,catalase (CAT) and superoxide dismutase (SOD) activities in alfalfa leaves,while there were no obvious effects on the malondialdehyde (MDA) content in alfalfa leaves. Appropriate Se-Zn and FA applied could significantly increase hay yield of alfalfa. The yield increasing effect of FA application was more obvious than that of Se-Zn fertilizer application,and Se-Zn and FA combined application had the best effect. Therefore,under the condition of sufficient supply of NPK,the appropriate amount of Se-Zn micro-element fertilizer or FA treatments could increase the antioxidant capacity of alfalfa and increase the hay yield,and appropriate Se-Zn and FA combined application had the best effect.