Estimating nutrient uptake requirements for soybean using QUEFTS model in China

Area of Science:

• Agricultural Science
• Agronomy
• Soil Science

Background:

• Optimizing soybean (Glycine max [L.] Merr) nutrition is crucial for enhancing yield and nutrient use efficiency in China.
• Accurate estimation of nutrient requirements is essential for developing effective fertilizer management strategies.

Purpose of the Study:

• To estimate the balanced nutrient requirements (nitrogen, phosphorus, potassium) for soybean in China.
• To assess the relationship between soybean seed yield and nutrient uptake.
• To validate the Quantitative Evaluation of the Fertility of Tropical Soils (QUEFTS) model for soybean nutrient management.

Main Methods:

• Collected field experiment data from major Chinese soybean-growing regions (2001-2015).
• Applied the QUEFTS model to simulate nutrient uptake curves and requirements for target yields.
• Analyzed nutrient removal in soybean seeds and above-ground parts.

Main Results:

• The QUEFTS model predicted a linear-parabolic-plateau curve for balanced nutrient uptake up to 6.0 t ha⁻¹.
• Producing 1000 kg of soybean seed requires 55.4 kg N, 7.9 kg P, and 20.1 kg K (N:P:K ratio of 7:1:2.5).
• Internal efficiencies were 18.1 kg/kg N, 126.6 kg/kg P, and 49.8 kg/kg K; seed removal accounted for 87.1% N, 74.1% P, and 60.8% K.

Conclusions:

• The study provides critical data for formulating precise fertilizer recommendations for soybean in China.
• The QUEFTS model is a reliable tool for estimating soybean nutrient requirements and guiding fertilizer application.
• Optimized nutrient management can improve soybean yield and resource use efficiency, minimizing deficiencies or excesses.