Effects of combined application of biogas manure and potassium fertilizer on antioxidant enzyme of maize leaf and soil enzyme activity

ObjectiveEffects of combined application of biogas manure and potassium fertilizer on the protective en-zymes in maize leaf of different genotypes and soil enzyme activity were studied to provide reference for the application of biogas manure and potassium fertilizer in planting of spring maize in northeast China.MethodZhengdan 958(com-pact type)and Fenghe 1(flat-unfolded type)were chosen as experimental materials. The experiment was carried out in pot under four treatments including A1(single application of biogas manure),A2(combined application of biogas manure and potassium fertilizer),A3(single application of potassium fertilizer)and CK(no fertilizer). The activity of antioxidant enzymes was detected 0,8,16 and 24 d after three-leaf period of maize,and that of soil enzymes was measured 0,10, 20 and 30 d after three-leaf period.ResultActivities of superoxide dismutase(SOD)and peroxidase(POD)in leaves of two tested maize varieties increased as the days spent under different fertilization treatments,and the increasing effects of SOD and POD activities on leaf were A2>A3>A1>CK. With the growth of maize seedlings,content of malondialdehyde (MDA)in leaves of two tested varieties increased gradually. Compared with CK,content of MDA in leaves under all treatments decreased on a whole,with that under A2 treatment the lowest. At the same time,with the increase of fertiliza-tion time,activity of invertase,catalase and urease of maize rhizosphere soil increased gradually,and the increasing ef-fects of different fertilization treatments on soil enzyme activity showed A2>A3>A1>CK.ConclusionAppropriate appli-cation of fertilizers can improve the protective enzyme activity in leaf of spring maize seedlings and invertase activity of maize rhizosphere soil,and the combined application of biogas manure and potassium fertilizer presents the optimal effect.