The effect of plant density on morphological traits and yield of four forage sorghum cultivars in Damghan region

To study the effect of plant density on morphological traits, dry fodder yield and yield components of four forage sorghum cultivars in second cropping, an experiment was conducted at experimental farm of Islamic Azad University of Damghan in 2012-13. A factorial randomized complete block design with three replications were used. The treatments were three plant density (88, 133 and 266 thousand plant per hectare) and four forage sorghum cultivars [Speed feed (early maturity), Sugergraze (medium maturity), Nectar (mid-late maturity) and Jambo (late maturity)]. The results showed that the effect of plant density on number of leaf per plant, leaf area index, number of tiller per plant, stem diameter, leaf, stem and panicle dry weight /per plant and/per m2, and dry fodder yield were significant. Dry fodder yeild was increased by 41.14 percent with increasing of plant density from 88 to 266 thousand plant per hectare. The result of this study showd that Sugergraze cultivar with plant density of 266 thousand plants per hectare is appropraite as second cropping in damghan region.