1、Nitrogen mobilization, nitrogen uptake and growth of cuttings obtained from poplar stock plants grown in different N regimes and sprayed with urea in autumn

Nitrogen mobilization, nitrogen uptake and growth of cuttings obtained from poplar stock plants fertigated with different nitrogen (N) treatments and sprayed with urea in autumn were studied.

2、Nitrogen fertilization has differential effects on N allocation and lignin in two Populus species with contrasting ecology

To obtain further information on the links between wood properties and nitrogen use in poplar, we studied wood histochemistry and composition as well as nitrogen partitioning in two poplar species grown with low or high nitrogen supply.

3、The effects of organic manure and chemical fertilizer on the growth and nutrient concentrations of yellow poplar

However, the effects of the mixed use of chemical fertilizer and organic manure on the growth of trees and soil fertility vary substantially according to the fertilizer amounts and the organic manure characteristics. The amount of organic manure required is mainly determined by the nitrogen content.

Role of Slow

One approach to improving the efficiency of phosphate and urea fertilization is to improve their interaction through nanocomposites that are able to control the release of urea and P in the...

Nitrogen

In this study, we analyzed the genome-wide transcriptional responses to N fertilization in the elongation zone (EZ) of P. trichocarpa.

Assessment of nitrogen fertilization for the CO2 balance during the production of poplar and rye

The overall goal is to obtain more verified information about the ecological drawbacks of nitrogen fertilization and to find out at what fertilizer rate the highest net CO 2 sequestration can be expected from the production of rye and poplar.

Foliar urea fertilization of cereals: A review

It has been suggested that there are several potential benefits of providing nitrogen to cereals via the foliage as urea solution.

The carbon bonus of organic nitrogen enhances nitrogen use efficiency of plants

Although oN may increase NUE compared to inorganic N fertilizers, as shown for urea (Arkoun et al. 2012), most agricultural practices rely on inorganic fertilizers.

Ecological effects of water and fertilizer addition on poplar

Abstract Read online ABSTRACT While irrigation and fertilization are basic cultivation practices in poplar plantations on a global scale, the impact of these practices on the environment is not well understood. Here, we demonstrate that water-urea addition and water-compound fertilizer addition differentially impact soil ecosystems. We report that water-fertilizer addition did not ...

Phosphorus and nitrogen physiology of two contrasting poplar genotypes when exposed to phosphorus and/or nitrogen starvation

Abstract. Phosphorus (P) and nitrogen (N) are the two essential macronutrients for tree growth and development. To elucidate the P and N physiology of wood

In agricultural cultivation, poplar trees, as vital avenue trees and urban greening species, rely on scientific fertilization for healthy growth. Both nitrogen fertilizers and urea are commonly used, but they play distinct roles in nutrient supply and growth. Below is a detailed comparison of these two fertilizers to guide optimal fertilization practices for poplar growers.

I. Roles and Characteristics of Nitrogen Fertilizers

Nitrogen fertilizers, one of the three essential macronutrients for plants, are crucial for poplar growth. They promote leaf development, enhance photosynthetic efficiency, increase biomass, and improve yield. Additionally, nitrogen fertilizers aid in flower bud differentiation and fruit production.

1. Types of Nitrogen Fertilizers

• Urea: A high-nitrogen, water-soluble, fast-acting fertilizer. Ideal for rapid nitrogen replenishment, urea is suitable as a topdressing fertilizer to accelerate growth and expand leaf area.
• Ammonium Sulfate: A medium-nitrogen fertilizer containing phosphorus and potassium. It improves soil water retention and structure, adaptable to diverse soil conditions.
• Ammonium Bicarbonate: A soluble nitrogen fertilizer quickly absorbed by plants. it should avoid contact with alkaline substances to prevent ammonia volatilization.

2. Fertilization Timing and Methods

• Spring Fertilization: Apply nitrogen fertilizers around bud break to boost new leaf growth and overall growth rates.
• Autumn Fertilization: Post-leaf-fall and before bud break, nitrogen application promotes flower bud differentiation for improved next-year fruiting.
• Topdressing: During summer heat, supplement nitrogen to offset nutrient losses. Control dosage to avoid root burn.

II. Characteristics and Application of Urea

Urea, a pure nitrogen fertilizer with 46% nitrogen content, is a cost-effective and efficient source. Its effects are prolonged but slower compared to other nitrogen forms.

1. Application Methods

• Direct Application: Use urea as basal or topdressing fertilizer by broadcasting, trench application, or soil mixing. Avoid mixing with alkaline materials to prevent reduced efficacy.
• Foliar Spraying: For nitrogen-demanding poplar varieties (e.g., nursery seedlings), foliar urea sprays rapidly boost nitrogen levels and leaf growth.

2. Precautions

• Avoid Overuse: Excessive urea can cause root burn or disease. Dosage should align with soil fertility and plant needs.
• Combine with Other Fertilizers: Pair urea with phosphorus, potassium, or organic fertilizers to balance nutrients and enhance efficiency.

III. Comprehensive Comparison and Recommendations

When selecting nitrogen sources for poplars, consider soil conditions, growth stages, and market demands. For general farms, urea is preferred due to its speed, cost-effectiveness, and accessibility. In nurseries or specialized settings, compound or organic fertilizers may provide broader nutritional support.

Optimal poplar fertilization depends on growth stage and soil status. Rational use of nitrogen fertilizers or urea improves yield, quality, and ecological sustainability.

Key Terms: Nitrogen fertilizer, urea, poplar trees, fertilization management, nutrient balance, sustainable agriculture.