Effect of Plant Density on some Morphological Traits and Quantitative and Qualitative Yeild of Forage Sorghum Hybrids in Golestan Province

To determine the effects of plant density on quantitative and qualitative yield of five forage sorghum hybrids, an experiment was conducted at Agricultural Research Station of Anbarloum in 2010 and 2011. The experiment was in factorial based on RCBD with four replications. The first factor was five hybrids of forage sorghum and the second factor was plant density with three levels (167000, 208000 and 278000 plantha-1). The results of analysis of variance showed that the effects of plant density and hybrids were significant on all of assesse traits. Mean comparison of the traits showed that with decrease in plant density, number of tillers per plant and stem diameter were increased. The highest number of tiller plant (3 tillerplant-1) was obtained from 167000 plant per hectare. In all hybrids, with increase in plant density, dry forage and protein yield were increased and the highest dry forage yield and protein yield were obtained from Speed Feed and ICRISAT 625 × R165 hybrids. Speed Feed produced the highest dry forage (18.5tha-1) and protein yield (132.5 kgha-1) in treatment with 287000 plant per hectare. Based on the results of this experiment, Speed Feed and ICRISAT625×R165 hybrids with 208000 plantha-1 dencity can be recommended for sowing in this region.