effect of plant density on yield, agronomic traits in new variety sunflower

in order to study the effect of plant density on yield and agronomic traits on new sunflower varieties in esfahan condition, an experiment was conducted in 2009 cropping season at agricultural research institute kabotar abads. the experimental design was factorial in a randomized complete block design with four replications. the experimental treatments were at 4 levels of plant density (6,8,10 and 12 plants/m2) and varieties (v1):arm.mok18-85, (v2):sire85-es, (v3):mok13-85, (v4):kc20/83es85. the results show that plant density significantly affected all of measured traits except oil percent. the effect of variety on all traits significantly affected except stem diameter, head diameter and seed number m2. the interaction between plant density and variety had significant on leaf area index, total dry matter, 1000 -seed weight, and seed yield. the highest and lowest seed yield obtained from density 12 plants/ m2 and variety (v1):arm.mok18-85 (3500/52 kg/ha) and 6 plants/m2 and variety (v2):sire85-es (2258 kg/ha) respectively.