The Effect of Tillage systems and plant densities on yield and yield components of soybean cultivars in Karaj condition

To study the effect of tillage systems and plant densities on yield and yield components of soybean cultivars, a field experiment as split split plot based on a randomized complete block design (RCBD), with three replications was carried out at Research Field of Faculty of Agriculture, University of Tehran, Karaj, Iran in 2015. The main plots were two tillage systems level (Conventional and No-till), plant densities (30, 45 and 60 plants per m2), as sub plots and three soybean cultivars (M9, Habbit and L17), were assigned in sub sub-plots. Results showed that tillage system had no effect on studied traits and the maximum pod number, grain number per plant, biologic yield and grain yield were obtained from 45 plants per m2. Habbit cultivar under no tillage system showed the highest grain yield that had no significant difference with L17 and M9 cultivars under conventional tillage and M9 under no tillage system. Maximum pod number per plant was obtained under conditional tillage with 45 plants per square meter in the L17 cultivar. Different studied cultivars have different actions to kind of tillage systems and this result showed the importance of selection of suitable cultivar under different tillage systems.