Conservation Tillage Effect as Residue Maintaining on Potato Yield

The effect of different seedbed preparation on potato yield, were studied in Agricultural Research Center of Semnan (Shahrood) in 2007-2009 periods. A RCBD based strip-block experiment with 4 replications was used, that horizontal factor included tillage methods as 1-Moldboard plowing, 2-Disk plowing, 3-fall chisel plowing and 4-spring chisel plowing and vertical factor included three potato cultivars (Agria, Deraga and Sante).Results of combined analysis (2007and 2009) showed, crop yield differences among tillage methods were significant, Maximum of tuber yield per hectare was related to spring chisel plowing (31.1t.ha-1).Soil inversion percent was significant among tillage treatments. Maximum and minimum of soil inversion percent was related to Moldboard plough (72/25%) and chisel plough (39.5%), respectively. Soil organic carbon was significant treatments among tillage methods. Maximum and minimum of Soil organic carbon was belonged to chisel (0.45%) and moldboard (0.28%) plowing, respectively. Regard to crop yield and chisel plough advantages, moldboard plough can be replaced with chisel plough.