KH2PO4-Based PK/UiO-66 Nanoparticles for Efficient Nutrient Delivery and Plant Growth Promotion of Pea Seedlings

Current agricultural foliar fertilization faces significant challenges such as poor nutrient retention and low utilization efficiency. To address this, we developed a nanoparticles-based foliar fertilizer, P and K-loaded nanoparticles (PK/UiO-66 NPs), using UiO-66 framework. The unique structure and properties of PK/UiO-66 NPs contributed to its superior performance in the field, ensuring prolonged nutrient supply to plants. The fertilizer demonstrated excellent foliar adhesion and washout resistance, allowing PK/UiO-66 NPs to continue supplying P and K nutrients to plants even after rainfall washout, thereby significantly enhancing plant growth. The stem length of pea sprouts increased by 20% and the photosynthesis rate by 17.6%, accompanied by highlight and activity. In addition, PK/UiO-66 NPs exhibited controlled-release characteristics, ensuring a steady nutrient supply over an extended period. This feature reduced nutrient losses and enhanced fertilizer utilization efficiency. PK/UiO-66 NPs released up to 62.3% of P after 48 h, whereas the KH2PO4 solution released over 90% of P within just 2 h. Transcriptomics analysis revealed that spraying PK/UiO-66 NPs regulated genes involved in pea growth, photosynthesis, and overall plant development, providing molecular insights into how the fertilizer modulates plant physiology. This study offers new perspectives on improving foliar spraying efficiency.