Effect of sulphur fertilizer and nitrogen split application on yield and its components of sunflower (Helianthus annuus L.)

In order to evaluate the effect of sulphur fertilizer and nitrogen split application on yield and its components of sunflower (Helianthus annuus L. ),an experiment was carried out at the research field of Birjand Faculty of agriculture in 2008 as factorial in complete randomized block design with three replicates.The treatments were sulphur fertilizer in four levels (0, 200, 400 and 800 kg/ha granular organic sulphur)and nitrogen split application in three levels(T1: 40 % at planting, 60 % at 6-8 leaves stage. ,T2: 40 % at planting,30% at 6-8 leaves stage, 30 % at budding stage., T3: 30 % at planting, 30 % 6-8 leaves stage, 20 % at budding stage,20 % at flowering).Results of variance analysis showed that sulphur had significant effect on all traits except harvest index.Increasing levels of granular organic sulphur up to 400 kg/ha caused an increase in head diameter,seed thousand weight,biological yield,seed yield and oil percent.Hollowness percent declined with 400 kg/ha sulphur treatment. Split application of nitrogen had significant effect on all traits except oil percent.Highest head diameter,seed number per head,seed thousand weight,harvest index and seed yield was obtained with third level and biological yield with second level of nitrogen split application but in all traits there was no significant difference between these two levels