Effects of Straw Returning with Different Tillage Patterns on Corn Yield and Nitrogen Utilization

To explore the effects of farming methods,straw returning and their interaction on corn yield and nitrogen utilization,the experiment was conducted for two consecutive years from 2016 to 2017 at the Xiangyang Experimental Base of Northeast Agricultural University in Heilongjiang Province of China.The method of combining farming with straw returning was used and six treatments as rotary tillage (R)+no straw returning (K),rotary tillage (R)+straw returning (S),tillage (T)+no straw returning (K),tillage (T)+straw returning (S),tillage (T)+subsoiling (D)+no straw returning (K) and tillage (T)+subsoiling (D)+straw returning (S) were set to study the effects of different tillage methods and straw returning on corn yield and nitrogen accumulation and utilization.The corn yield,nitrogen accumulation,nitrogen transport,grain weight and dry matter accumulation of tillage (T)+subsoiling (D) and tillage (T) were significantly higher than those of rotary tillage (R) treatment.Meanwhile,the corn yield,nitrogen accumulation and dry matter accumulation of TD treatment were significantly higher than those of T treatment;the corn yield,dry matter accumulation,kernel weight,nitrogen dry matter production efficiency and nitrogen grain production efficiency of S treatment were significantly higher than those of K treatment.Among the treatments,the yield,nitrogen accumulation and utilization efficiency of TDS,TS and TDK were the highest.The yield,nitrogen accumulation and nitrogen transport of TDS were significantly higher than those of TS.In 2016,TDS production increased by 7.30% and 8.20% compared with TS;and TDS nitrogen accumulation increased by 6.78% and 9.50% compared with TS,while the yield and nitrogen grain production efficiency were significantly higher than those of TDK.Therefore,under the conditions of this experiment,on the basis of straw returning,tillage+subsoiling was the suitable farming method.