NY/T 3552-2020 in English

Interpretation of the core content of the standard

This standard establishes a complete technical framework for the field trial of macro-element water-soluble fertilizers, focusing on regulating three major links:

Key technical points

1. Experimental design specifications

Set the area of the plot according to the difference in crop types:

• Densely planted crops: 20-50m² (low value for rice/wheat, high value for corn/cotton)
• Protected vegetables: ≥15m² and ≥3 beds
• Fruit trees: ≥4 plants or 40m², the consistency of tree age must be ensured

2. Data analysis methods

The analysis of variance (F test) combined with LSR/LSD multiple comparisons was used. The evaluation indicators included:

Implementation Suggestions

Operation Precautions

1. Soil sampling strictly follows the NY/T 1121.1 standard to determine basic indicators such as organic matter, available nutrients, and pH value
2. Perennial crop experiments need to last for more than 2 years to avoid the impact of inter-annual climate differences
3. Drip irrigation test needs to record the EC value of irrigation water to prevent water quality from interfering with the results

Economic benefit evaluation model

It is recommended to use the following formula for calculation:

Input-output ratio = (increased output value of fertilization - fertilization cost) / fertilization cost

The increased output value is calculated based on the local average market price of agricultural products