Effects on Yield of Winter Wheat and Soil Physical-Chemical Properties Under Different Conservation Tillage

There were four treatments in field conditions: Conventional tillage(CT)、Straw returning no-tillage(NT1)、All-pole straw returning no-tillage(NT2) and Straw returning and subsoiling no-tillage(NTS),and the effects on soil physical-chemical properties and yield of winter wheat were studied under conservation tillage.The results showed that after returning green stage,the soil bulk density of 0～20cm under conservation tillage was lower than CT treatmen,organic matter content、available nitrogen、available potassium and available phosphorus content were higher than CT treatmen,but the soil indexes of 20～40cm,in addition to NTS performed the same trend,NT1 and NT2 performed decreasing tendency.Conventional tillage got higher grain number per spike and 1000-grain weight,however,decreased spike number,it was 240 million/hm2 less than conventional farming.The performance of the yield was as follow: NTS was the highest,then CT and NT2,and NT1.It shows that if subsoiling technique and straw returning are combined,it can effectively improve and enhance the soil physical-chemical properties in the topsoil layer and the following topsoil layer,develop the yield potential efficiently under conservation tillage.