Effect of Foliar Application of Boron, Zinc and Manganese on Growth, Yield and Oil Contents of Sunflower (Helianthus annuus L.)

A field trial was conducted to assess the effect of exogenously applied boron, zinc and manganese on growth, yield and oil contents of sunflower at Research Area, University of Agriculture, Faisalabad during Spring, 2019. Randomized Complete Block Design (RCBD) was used for the allocation of treatments with 3 replications. Seed was sown using dibbler on 75 cm apart ridges. Foliar treatments included T0= Control, T1= Water spray, T2= 0.6% boron (B), T3= 0.6% zinc (Zn), T4= 0.6% manganese (Mn), T5= 0.3% B+0.3% Zn, T6= 0.3% B+0.3% Mn, T7= 0.3% Zn+0.3% Mn and T8= 0.2% B+0.2% Zn+0.2% Mn). Boron, Zinc and Manganese were sprayed at 35 days and 55 days after sowing keeping Borax (H3BO3), Zinc Sulphate (ZnSo4) and Manganese Sulphate (MnSo4) as sources of B, Zn and Mn, respectively. Various phenological, physiological and agronomical traits were monitored and analysed. Spray of 0.2% B+0.2% Zn+0.2% Mn gave the high values of traits including number of achenes per head, 1000-achene weight (g), achene yield (kg ha-1), biological yield (kg ha-1), harvest index (%), oil yield (kg ha-1) and achene-oil content (%).