Evaluating reduced tillage methods on energy productivity and

rainfed wheat yield

The so-called reduced tillage is one the most important management practices for soil and water conservation. In order to study the effect of reduced tillage on energy productivity and wheat yield in Kalpoush region of Shahrood، a randomized complete blocks design (RCBD) experiment with sunflower-wheat rotation was conducted having five treatments and four replicates. The treatments were consisted of chisel plowing at spring + disking (T1)، moldboard plowing +disking (T2)، reduced tillage with disk harrow (T3)، disk plowing + disking (T4) and chisel plowing at autumn +disking (T5). Sunflower was planted at May 2008 and 2011. After harvesting at October 2008 and 20، all plots were disked. Wheat was planted at November 2008 and 2011 and harvested at July 2009 and 2012. The results showed that there was no significant difference among the treatments (P<5%). In 2009 the maximum (1708 kg/ha) and minimum (1412 kg/ha) crop yield were belonged to T5 and T3 treatments، respectively. In 2011، the maximum (1638 kg/ha) and minimum (1388 kg/ha) yield was obtained from T5 and T2 treatments، respectively. Further data analysis showed that soil water content and wheat yield differences are not significant among the treatments (P<5%). The maximum and minimum soil moisture and wheat yield related to chisel and moldboard ploughs، respectively. Maximum and minimum energy productivity was related to disk harrow and moldboard ploughs، respectively. Chisel plugging increased the wheat yield. Soil inversion index difference was significant among the treatments (P<1%). Maximum and minimum soil inversion index related to moldboard and chiselploughs، respectively. Considering disk harrow advantages and results of this experiment، for wheat production it may be recommended that plowing can be replaced by disk harrow، disk harrowing for seedbed preparation is sufficient، and plowing isn’t required.