Biological sciences

The impact of different forms of nitrogen applied externally on rice growth and nitrogen accumulation is crucial for maximizing crop yield and improving nutrient use efficiency. Various nitrogen sources—like nitrate (NO₃⁻), ammonium (NH₄⁺), and urea—affect rice plants in unique ways, influencing their growth rates, biomass production, root development, and nitrogen uptake efficiency. As a semi-aquatic plant, rice tends to favor ammonium as its nitrogen source in flooded environments, where it remains more stable in low-oxygen soils. When ammonium is utilized, rice plants typically exhibit enhanced growth and yield due to their ability to efficiently assimilate this form. On the other hand, nitrate and urea can also be advantageous in well-drained, aerobic conditions, as they promote root development and enhance nutrient uptake. Urea, a widely used nitrogen fertilizer, offers a consistent release of nitrogen, but its conversion to ammonium and nitrate in the soil is influenced by factor...