Optimizing the P balance: How do modern maize hybrids react to different starter fertilizers?

Area of Science:

• Agricultural Science
• Plant Breeding
• Soil Science

Background:

• Phosphorus (P) is a vital plant nutrient, yet globally scarce.
• European Union regulations restrict fertilizer use due to environmental concerns.
• Maize often requires P starter fertilizer, but reducing this input is desirable.

Purpose of the Study:

• To assess the potential for breeding high-performing maize hybrids with reduced P starter fertilizer.
• To evaluate the impact of different starter fertilizers on maize growth and yield.
• To identify maize genotypes suitable for low-P conditions.

Main Methods:

• Multi-location field trials with 20 commercial maize hybrids in Germany.
• Evaluation of three starter fertilizers: triple superphosphate (TSP), calcium ammonium nitrate (CAN), and diammonium phosphate (DAP), plus a control.
• Assessment of various traits from early development to grain yield.

Main Results:

• Diammonium phosphate (DAP) significantly increased yield by +0.67 t/ha (+5.34%) over the control.
• Genotype-by-starter fertilizer interactions were non-significant, indicating consistent hybrid performance across treatments.
• Grain yield showed a negative correlation with grain P concentration, suggesting a dilution effect.

Conclusions:

• Maize hybrids can be bred for improved P efficiency, allowing for reduced starter fertilizer application.
• Selecting high-performing genotypes is feasible regardless of the starter fertilizer used.
• Findings support strategies to decrease starter fertilizer use in maize cultivation.