effect of different tillage methods on some soil physical properties and dryland wheat yield in rotation of chickpea- wheat in hamedan province

dryland winter wheat (triticum sativum l.) generally grown in rotation with fallow or chickpea (cicer arietinum l.) constitutes a major crop in the west region of iran. information is limited on the success of more intensive dryland cropping systems while applying conservation tillage management. an experiment was conducted to determine the effect of five tillage systems on soil physical properties and on crop yield in a winter wheat-chickpea rotation during a 4-year period on a silty clay loam in tajarak research station (kaboudarahang township), hamedan. tillage treatments were comprised of conventional tillage (ct: mouldboard plow + disk), reduced tillage (rt: chisel plow + roller packer), minimum till (mt: sweep plow + roller packer), cyt: cyclotiller + roller packer and no-till (nt: direct planting). a randomized complete block design of four replications was employed. some soil physical properties including: bulk density and permeability were assessed. also wheat yield and yield components were determined. tillage treatments exerted significant effects on bulk density and permeability. rt exhibited lower bulk density and higher permeability among treatments. mean grain yields over the three seasons were recorded as 1050 kg ha−1 for rt, 1030 kg ha−1 for cyt, 982 kg ha−1 for mt, 974kg ha−1 for nt and 932 kg ha−1 for ct. average grain yields while applying conservation tillage were greater than those using ct treatment. this study revealed that a wide range of conservation tillage systems are adaptablefor an intensive dryland cropping systems for the semiarid areas of hamedan. therefore the traditional system of applying moldboard plow, following chickpea cultivation could be replaced by conservation tillage systems that can increase yield and will likely improve soil properties in the long run.