Enhancing crop yield and quality on marginal soils through fertilization strategies with selenium and silicon applications

Abstract . A three-year field trial aimed to evaluate the influence of various fertilization strategies - i.e., mineral, organic, and combined applications - on yield, nutrient use efficiency, and quality of three cereal crops (spring barley, spring oats, and winter rye) grown on Lithuanian marginal sandy soils. The effectiveness of foliar selenium (Se) and silicon (Si) applications in enhancing crop nutritional quality and productivity was also assessed. Mineral fertilization significantly increased grain yield and nutrient uptake compared to organic and unfertilized treatments, with N being the primary limiting nutrient. However, integrated fertilization (mineral + compost) produced similar grain yields and offered promise for long-term soil improvement. Winter rye exhibited the highest N use efficiency (∼70%), while oats had the lowest (∼33%). P and K use efficiencies were considerably lower across all crops. Selenium application enhanced Se accumulation in grains and leaves, indicating successful biofortification without negatively impacting macro-nutrient uptake. In contrast, Si did not affect grain yield and nutrient use efficiency. Overall, the results highlighted the importance of balanced and crop-specific fertilization strategies in improving productivity and nutrient efficiency on low-fertility soils, while also exploring the potential of micronutrient biofortification to improve grain quality. • Crop response to fertilization varied greatly by species and year • Mineral fertilization significantly increased cereal yield on marginal sandy soil. • Organic–mineral combinations achieved similar yields and improved soil properties. • Si foliar application had no consistent effect on yield or nutrient efficiency. • Se application enhanced grain Se without affecting macronutrient uptake