Optimization of Nitrogen and Phosphorus Fertilization for Improving Sugarcane Yield and Sucrose

Abstract

Nitrogen (N) and phosphorus (P) are the most critical macronutrients limiting sugarcane (Saccharum officinarum L.) productivity and sucrose accumulation. Nitrogen drives vegetative growth, photosynthetic capacity, canopy development, and stalk elongation, while phosphorus is essential for early root establishment, tillering, energy transfer (ATP), and sucrose metabolism. However, low nutrient use efficiency, rapid P-fixation in tropical soils, and imbalanced application often result in suboptimal yields and environmental concerns such as nitrate leaching and N₂O emissions. Optimal management follows the 4R Nutrient Stewardship principles (Right source, rate, time, and place) with recommended N:P₂O₅: K₂O ratios around 5:1:5 and split N applications aligned with crop demand. Combined N and P fertilization enhances enzyme activities (e.g., SPS for sucrose synthesis), delays senescence, improves root architecture, and increases cane yield, sugar recovery, and stalk quality. Integration of controlled-release fertilizers, nitrification/urease inhibitors, phosphate-solubilizing bacteria, and precision agriculture tools (VRT, grid sampling, UAV monitoring) further boosts efficiency while reducing losses. This review synthesizes physiological, biochemical, and agronomic evidence to establish best practices for maximizing sugarcane yield and sucrose content while promoting sustainable nutrient management in diverse agro-ecological zones.