Comparative study on the effect of foliar application of micronutrients on growth, yield and seed oil content of sunflower (Helianthus annuus L.)

In order to study the effect of foliar micronutrients application on quantitative and qualitative characteristics of sunflower, an experiment was conducted in research field of Islamic Azad University, Varamin Branch in Iran during 2011 growing season. The experimental design was laid out in a randomized complete block in four replications. The factor in this study included foliar micronutrients application (Fe+Zn+Mn+B) in six levels (non-foliar application, foliar micronutrients application within emergence stage, pollination stage, initial maturity stage, maturity stage and all growth stages). The result showed that foliar micronutrient application increased plant height, cap diameter, seed number in cap, 1000-seed weight, seed yield, biological yield, harvest index, oil percentage and oil yield in all growth stages. The results obtained here suggest that foliar micronutrients application can improve the seed yield and seed quality of sunflower grown under irrigation condition.