1、Nitrogen Fertigation of Young Navel Oranges: Growth, N Status, and

Results suggest that N applications are not needed during the first growing season after planting for microsprinkler-irrigated citrus in Arizona. Only low rates of N (≤68 g/tree/yr) may be needed during the second growing season to maintain adequate tree N reserves.

2、Long

Soil total nitrogen (N) and mineral N were significantly higher in the middle-aged and mature orchards than in the young orchard.

3、Navel orange fine root nutrient content and rhizosphere effects varied

Soil nutrients provide essential nutrients and mineral elements for navel orange tree growth, fruit yield, and fruit quality.

4、Effects of Combined Application of Organic and Inorganic

In 2020， a pot experiment simulating water-fertilizer integration was carried out by times of artificial pouring water and fertilizer under the equal nitrogen input.

5、Step

Navel orange trees require essential nutrients for optimal health. Nitrogen promotes leaf growth and overall vigor, phosphorus supports root development and flowering, and potassium enhances fruit quality and disease resistance.

The influence of nitrogen fertilizers on nitrate accumulation in leaves

Nitrogen fertilizers have a crucial importance in citrus fertilization, which is caused, on the one hand, by the large demand for nitrogen of citrus plants and on the other hand, by the nitrogen poverty of red soil and organic soil.

Effect of nitrogen level application on yield and fruit quality of

The objective of the present paper was to evaluate the effect of nitrogen level on yieldand fruit qualityof citrusand to determine the optimum N fertilizer ratesof Navel...

Improving Yield and Fruit Chemical Properties in Washington Navel

2.1. Experimental design and tested treatments A- Nitrogen fertilizers: used four different treatments of nitrogen fertilizers were as follows: the first week of March (early spring) of both seasons, trees received 100 kg/feddan of calcium nitrate. Another 50 liter/feddan of nitric acid added set fertilization w

Effect of Different Levels and Sources of Nitrogen on Tree Growth

Nowadays, the modern agricultural production system emphasizes the use of a lower amounts of chemical N fertilizer for plant nutrition. Large amounts of N are depleted annually from the soil as a result of heavy crop productivity and pruning of shoots and leaves.

Effects of Nitrogen Fertilizer of Different Forms and Ratios on

Under mixed supply of sodium nitrate and NH4+-N, the plant growth, nitrogen absorption amount and nitrogen use efficiency were decreased when the ratio of sodium nitrate increased, the ammonia poisoning phenomena happened in the root system of navel orange young trees when using NH4+-N or CO (NH2)2 alone.

As an important cash crop, navel oranges have strict nutritional requirements during their growth. Nitrogen, a primary nutrient for plant development, plays a critical role in their growth and development. Applying an appropriate amount of nitrogen fertilizer can promote leaf growth, enhance photosynthesis, improve disease resistance, and increase fruit quality and yield. excessive nitrogen application may lead to nutrient imbalance, rapid growth, and other issues. rational use of nitrogen fertilizer is key to ensuring healthy navel orange growth.

I. The Role of Nitrogen Fertilizer in Navel Orange Growth

1. Promoting Leaf Growth Nitrogen is a key component of chlorophyll, essential for leaf development and differentiation. During the early growth stages, moderate nitrogen fertilization accelerates leaf expansion, providing sufficient nutrients for the plant. As the plant matures, nitrogen demand increases, requiring timely adjustments to fertilizer amounts to meet its needs.

2. Enhancing Photosynthesis Nitrogen is a vital raw material for photosynthesis, participating in the synthesis of enzymes critical to the process. Proper nitrogen application improves photosynthetic efficiency, increases net photosynthetic rates, and ultimately boosts fruit quality and yield.

3. Promoting Root Development Nitrogen also impacts root growth. Moderate nitrogen fertilization strengthens root systems, enhancing water and nutrient absorption, which benefits overall plant development.

II. Principles for Applying Nitrogen Fertilizer

1. Apply in Small Amounts and Multiple Times Nitrogen should be applied in divided doses rather than large quantities at once. This prevents soil nitrogen accumulation, reduces wastage, and ensures a steady supply of nutrients to the plant.

2. Combine with Phosphorus and Potassium Fertilizers Nitrogen works synergistically with phosphorus and potassium. Phosphorus fosters root and fruit development, while potassium enhances stress and pest resistance. Balancing these nutrients optimizes fertilizer efficiency and addresses the plant’s diverse needs.

3. Adjust Based on Soil Conditions Soil type and pH influence nitrogen requirements. Conduct soil tests to determine nitrogen levels and acidity. Acidic soils benefit from sulfur- or ammonium-containing fertilizers, while alkaline soils suit nitrate-based formulas.

III. Precautions for Nitrogen Application

1. Avoid Overapplication Excessive nitrogen disrupts nutrient balance, causes rapid growth, and reduces fruit quality. Carefully control dosages to prevent overuse.

2. Prevent Leaching Losses Unused nitrogen may leach into soils during rain, leading to waste and environmental harm. Cover fertilized soil promptly to minimize loss.

3. Consider Environmental Factors Adjust nitrogen amounts based on climate. Drought-prone areas may require more nitrogen, while humid regions need less to avoid buildup. Monitor weather patterns to refine fertilization strategies.

Nitrogen fertilization is essential for navel orange growth, but excessive use poses risks. To ensure healthy development, apply nitrogen judiciously, considering plant stage, soil conditions, and environmental context. By balancing these factors, growers can maximize yields while maintaining ecological sustainability.