| In order to solve the problems of high N fertilizer application rate,low utilization rate of livestock manure in northeast China,field experiments with different liquid dairy manure and N fertilizer rates was conducted.Treatments were as followed,conventional fertilizer（T1）,no fertilizer（T2）,fermented liquid cow manure 67.5t·hm-2（T3）,fermented liquid cow manure67.5t·hm-2 with 40%N reduction（T4）,fermented liquid cow manure 135t·hm-2 with 20%N reduction（T5）,fermented liquid cow manure 135t·hm-2with 40%N reduction（T6）and fermented liquid cow manure 135t·hm-2 with 40%N reduction（T7）,20%N reduction with fermented liquid cow manure 67.5 t.hm-2（T5）,135 t.hm-2（T6）,40%N reduction with fermented liquid cow manure135 t·hm-2（T7）,and 20%N reduction with fermented liquid cow manure 135 t·hm-2（T8）.Dry matter,N,P and K accumulation,grain yield,fertilizer utilization efficiency,and soil heavy metal accumulation were studied.To investigate the agronomic effects of liquid manure and chemical fertilizer application on spring corn production,and to provide theoretical basis and application techniques for scientific application of liquid manure and chemical fertilizer.Main results are as followed.（1）Compared with T1,Application of fermented liquid cattle manure with 20%reduction in nitrogen fertilizer could effectively increase the dry matter accumulation of maize.The application of liquid dairy manure promoted dry matter accumulation.The accumulation of N,P and K at maturity was increased by 65.1%and 67.1%,31.6%and 35.7%,75.1%and 49.4%in T5 and T8treatments,respectively,compared to T1 treatment.（2）Application of 135t·hm-2 of fermented liquid dairy manure with 20%nitrogen reduction obtain the highest seed yield of 10.8 t·hm-2 and the T3-T8 treatments increased 100 grain weight by4.5%-12.3%,yield by 1.67%-12.03%,crude fat content by 2.6%-7.8%,crude protein content by1%-12.7%,and starch content by 0.2%-3.8%compared with the farmers’conventional treatments.The crude fat content increased by 2.6%-7.8%,crude protein content increased by 1%-12.7%,starch content increased by 0.2%-3.8%.（3）Application of fermented liquid dairy manure effectively increased the nitrogen use efficiency,nitrogen partial productivity and total nitrogen contribution rate.Compared with T1,the nitrogen use efficiency,nitrogen partial productivity and total nitrogen contribution rate of T5 and T8 treatments increased by 107.1%and 49.9%,36.0%and 79.8%,82.3%and 113.0%.（4）Liquid dairy manure with reduced nitrogen application can improve fertilizer N utilization,fertilizer N partial productivity.Grain yield could be improved by liquid dairy manure with proper application rate.Highest economic profit was obtained under 67.5t·hm-2 with 20%reduction nitrogen fertilizer with an earning of 1111.38 yuan per hectare.（5）The application of fermented liquid dairy manure to reduce the application of nitrogen fertilizer does not cause heavy metal pollution problems to the soil,and the soil Cd,Hg,Pb,Cr,Ni,Cu,As and Zn contents are more less than national safety standards,and the heavy metal content of the seeds met the requirements of China’s food safety standardsCollectively,the 20%N reduction with 135 t·hm-2 fermented liquid dairy manure had positive effects on corn growth under the conditions of this experiment.It effectively increased maize dry matter accumulation,improved maize N,P and K accumulation,promoted maize nutrient uptake,facilitated seed accumulation,and delivered nutrients to seeds efficiently in the late reproductive stage,improving seed quality and thus maize yield.However,considering the application cost of fermented liquid cattle manure,the application of 67.5 t·hm-2 of fermented liquid cattle manure with20%nitrogen reduction has high economic efficiency and does not cause heavy metal pollution problems to the soil. |
PDF Full Text Request