Effect of Plant Density on Yield and Quality Traits of Four Sunflower Genotypes

In order to determine the effect of plant density on yield and qualitative traits of four genotypes of sunflower (Helianthus annuus L.) an experiment was conduct in Research Farm of Kabotar Abad, Isfahan province, Iran, in 2009. The statistical design was factorial arrangement in complete randomized blocks with four replications. Four plant density (6, 8, 10 and 12 plants/m2) and four genotypes of sunflower (Arm-mok18-85, S1R-85-ES, MOK13-85 and KC20/83ES85) were considered. The results indicated that the effect of plant density was significant on all measured traits except oil percentage, ratio of nut to seed coat, protein percentage and number of days to physiological maturity. The effect of genotype was significant on all traits except head diameter, number of seeds per m2, oil yield, protein percentage and harvest index. Interaction of plant density and genotype was significant on oil yield, biologic yield and number of days to physiological maturity (p<0.01). The highest yield (3500.52 kg/ha) was produced in by plants/m2 and Arm-mok18-85 genotype. In general, results indicated that there was no significant difference for seed yield between 10 and 12 plants/m2 densities. Therefore, to decrease seed consumption, it seems that 10 plants/m2 could be recommended.