1、Fertilizer placement to improve crop nutrient acquisition and yield: A review and meta

Fertilizer placement in soil, which refers to precise application of specific fertilizer formulations close to seeds or plant roots to ensure high nutrient availability, may be a more effective alternative to broadcast application.

2、A plan for efficient use of nitrogen fertilizers

A global analysis finds that nitrogen fertilizers could be used more efficiently if their international distribution across croplands was altered — a measure that would also decrease nitrogen...

3、Phosphorus and Potassium Fertilizer Application Strategies in Corn–Soybean Rotations

Determining optimum application rates and timings for these fertilizers has been an ongoing research focus for decades and efforts continue to refine recommendations.

"Optimization of nitrogen and phosphorus fertilizer timing and placemen" by Martha R Winters

Different strip-tillage timings (fall, spring, or fall and spring) and nutrient placements (zone-banded or surface broadcast) were compared both with and without starter (N and P) fertilizer applications during the precision-guided corn planting operation.

The application timing of nitrogen fertilizer

This paper shows that a split application of nitrogen fertilizer is an optimal strategy for both risk-neutral and risk-averse cotton farmers in the United States if there is a possibility that they may be unable to apply nitrogen fertilizer after planting.

Nitrogen and phosphorus losses and eutrophication potential associated with fertilizer application to cropland in China

Increased application of nitrogen (N) and phosphorus (P) fertilizer has significantly improved crop yields and food security in China over the past several decades. However, this has also led to serious problems of aquatic eutrophication in inland and coastal waters.

Nitrogen, Phosphorus, and Potassium Flows through the Manure Management Chain in China

Herein, we present a detailed analysis of the nutrient flows and losses in the “feed intake–excretion–housing–storage–treatment–application” manure chain, while considering differences among livestock production systems.

Full article: Optimizing nitrogen application timing at key leaf stages to enhance yield for high

The findings will contribute to the optimization of nitrogen fertilizer management strategies for high-density DSR, supporting the development of high-yield and environmentally sustainable rice production systems within rice-wheat rotations in the lower reaches of Yangtze River, China.

Lu, C; Tian, H (2016): Half

We therefore develop a global time-series gridded data of annual synthetic N and P fertilizer use rate in croplands, matched with HYDE 3,2 historical land use maps, at a resolution of 0.5º latitude by longitude during 1900-2013.

Timing Nitrogen Fertilizer Application to Reduce Nitrogen Losses to the Environment

Huang, W. Y, Uri, N. D. and Hansen, L.: 1993, Timing Nitrogen Fertilizer Applications to Reduce Nitrogen Losses: Assessing a Farmer's Decision on Application Timing, U.S. Department of Agriculture, Economic Research Service, Washington, DC.

The timing of applying high-nitrogen, high-phosphorus fertilizer to grapes is critical for improving yield and quality. Below is a detailed explanation of the optimal timing, methods, and precautions for foliar fertilization:

I. Optimal Fertilization Timing

1. Early Growth Stages

• Budbreak Stage: During the initial budbreak phase, when roots are just beginning to develop and nutrient demands are low, fertilization promotes root growth, laying a foundation for subsequent development.
• Pre-Flowering Fertilization: Applying high-nitrogen, high-phosphorus fertilizer before flowering enhances flower bud formation, ensures smooth blooming, and improves pollination and fruit-setting rates, thereby increasing yield.

2. Fruit Enlargement Stages

• Post-Initial Bloom to Rapid Fruit Enlargement: This is a critical period for rapid grape enlargement. Fertilization during this stage meets the nutritional demands of developing fruits, promoting growth and quality.
• Post-Bloom to Ripening: Continued use of high-nitrogen, high-phosphorus fertilizer from post-bloom to maturity boosts sugar accumulation and flavor compound development, enhancing fruit quality.

II. Fertilization Methods

1. Soil Testing

• Soil Analysis: Conduct soil tests before fertilization to determine nutrient levels and soil conditions, ensuring precise fertilizer types and quantities.
• Fertilizer Selection: Choose appropriate high-nitrogen, high-phosphorus fertilizers (e.g., urea, diammonium phosphate) based on soil test results. Avoid overapplication to prevent waste or environmental contamination.

2. Application Techniques

• Trench Application: Evenly spread fertilizer over the soil surface, then deeply incorporate it to ensure thorough mixing. Suitable for large vineyards.
• Hole Application: Place fertilizer directly near the root zone or under the canopy, then cover with soil. Ideal for smaller vineyards or potted grapes.

III. Precautions

1. Fertilizer Types

• Combine Organic and Chemical Fertilizers: Organic fertilizers improve soil structure and nutrient availability, while chemical fertilizers provide quick nutrient replenishment. Combining them optimizes grape growth.
• Balanced Formulations: Tailor fertilizer types and concentrations to grape growth stages and soil conditions for best results.

2. Application Rates

• Moderation: Adjust fertilization amounts based on grape health and soil conditions to avoid overuse, resource waste, or environmental harm.
• Split Applications: Apply fertilizer in multiple stages rather than in a single heavy dose to prevent soil salinization or root damage.

3. Timing

• Morning Application: Fertilizing in the morning reduces water evaporation, improves nutrient absorption, and minimizes pest/disease risks.
• Evening Application: Evening fertilization avoids high temperatures that degrade nutrients and reduces pest/disease incidence.

applying high-nitrogen, high-phosphorus fertilizer to grapes requires careful consideration of timing, methods, and environmental factors. By combining scientific practices, balanced fertilizer use, and mindful timing, growers can maximize yield, enhance quality, and achieve sustainable viticulture goals.