The effect of plant density on yield and its components in three rain fed barley cultivars

An experiment was conducted to determine the effect of five plants densities (100,200,300,400 and 500 grain m-2) on yield and its components in three rain fed barley cultivars (Ezeh, Mahor and Dopar). A factorial experiment based on randomized complete block design with three replications was conducted in agricultural research center of khorramabad city in the east of Iran (in 2006-2007). In this experiment the correlation between traits and the traits that had the greatest effect on grain yield was determined. Direct and indirect effects on yield traits were analyzed. The results showed that there was significant difference among cultivars in term of grain yield and interaction effect of cultivars and plant densities on grain yield was significant among different plant densities were not significant differences. Mahor cultivar in 100 grain m-2 treatment had the highest grain yield (6633 kg ha-1). The correlation coefficient between grain yield and biological yield, straw yield, Harvest index, hectoliter weight and numbers of spike per square was positive and significant but correlation coefficient between grain yield and flag leaf length and grain filling rate was negative and significant. The results of path analysis indicated that four characteristics including hectoliter weight, thousand kernel weight, numbers of grain per spike and numbers of spikes per square were main yield components for grain yield. Based on the results of path analysis among studied characteristics there was the most direct effect among the number of spikes m-2 (r=1.48**) and number of grain spike-1 (r=1.40**) with grain yield. The results showed that 300 grain m-2 treatment for barley cultivars can be recommended in rain fed condition.