Assessing the Role of Liquid Fertilizer Applications on Sunflower Yield and Nutrient Uptake Under Varying Moisture Conditions During Critical Growth Stages in Thrace

This study evaluated the effects of liquid versus solid fertilizer applications on sunflower yield and nutrient uptake under contrasting rainfall conditions. Field trials were conducted in Kırklareli (sufficient rainfall, SR) and Keşan (insufficient rainfall, IR). Fertilizers containing nitrogen, phosphorus, and potassium (20-20-0, 15-15-15, and DAP) were applied in both liquid and solid forms. Under SR conditions, liquid fertilizers significantly increased sunflower yield, biomass, and the uptake of key macronutrients (N, P and K) and micronutrients (Zn, Fe and Cu) compared to solid fertilizers. However, under IR conditions, neither liquid nor solid fertilizers provided a significant improvement in yield or biomass. These findings highlight that liquid fertilizers are effective in enhancing sunflower productivity and nutrient acquisition under adequate moisture conditions but have limited impact under drought conditions.