Long-Term Year-Interval Effect of Continuous Maize/Soybean Intercropping on Maize Yield and Phosphorus Use Efficiency

Area of Science:

• Agricultural Science
• Agronomy
• Soil Science

Background:

• Global food demand and land degradation necessitate sustainable agricultural intensification.
• Maize-soybean intercropping offers potential for increased yields and land use efficiency.
• Long-term effects of continuous intercropping on yield, phosphorus use efficiency (PUE), and sustainability are not well understood.

Purpose of the Study:

• To evaluate the year-interval effects of continuous maize/soybean intercropping on maize yield, PUE, and sustainability.
• To compare intercropping performance against maize monocropping over a seven-year period.
• To provide insights for enhancing food security and nutrient management.

Main Methods:

• A seven-year field trial (2017-2023) on acidic soil.
• Comparison of maize monocropping versus maize-soybean intercropping systems.
• Analysis of yield, phosphorus use efficiency metrics (AE, RE, PFP, CPF), and sustainability.

Main Results:

• Continuous maize-soybean intercropping consistently outperformed maize monocropping across all year intervals.
• Maize yield increased by 37% (year 1), 35% (year 3), and 58% (year 7), with a 55% average increase over seven years.
• Intercropping significantly enhanced PUE metrics (AE, RE, PFP, CPF), with the seventh year interval showing substantial improvements.

Conclusions:

• Continuous maize-soybean intercropping is a viable strategy for enhancing maize yield, PUE, and sustainability.
• The seventh year of intercropping demonstrated the most significant positive impacts.
• Findings support improved food security and nutrient management through sustainable intercropping practices.