كليدواژه :
growth analysis , تراكم گياهي , Spring wheat , شاخص رشد , Variety , عملكرد , Yield , كشاورزي , Density , گندم
چكيده لاتين :
In order to investigate the effect of varieties and plant densities on dry matter accumulation (DMA), crop growth rate (CGR), relative growth rate (RGR), and grain yield, an experiment was conducted in 1999 at the Agricultural Research Station, Tabriz University .In this study, six spring wheat varieties (Falat, Gods, Chamran, Darab-2, Tajan and Backcross Roshan )and four planting densities (400,450,500 and 550 plant m^-2 )were evaluated, using a randomized complete block design with split- plot layout and three replications. Varieties were assigned to the main plots and planting densities to sub plots. Analysis of variance of data showed that varieties and densities had significant effect on biomass yield at 1% and 5% levels of probability respectively. The effect of densities on grain yield and also the effect of variety * density interaction, on both biomass and grain yield, were not significant. Plant growth analysis, based on growing degree day (GDD), also showed that there were significant differences between varieties for DMA, CGR and grain yield. DMA and CGR increased when growing degree days increased using highest seeding densities. The effect of plant densities on DMA, CGR, RGR, and growth and developmental stages of cultivars were not significant. The highest values for DMA, CGR and RGR in all varieties were obtained at 550 . plant /m^2. "Gods" produced highest DMA, CGR, RGR , biomass -and ,grain yield at this plant density than other varieties.
