Fertilizer efficiency in wheat is reduced by ozone pollution

Area of Science:

• Agricultural Science
• Environmental Science
• Plant Physiology

Background:

• Inefficient fertilizer use leads to nutrient leaching and environmental contamination.
• Ground-level ozone is an environmental stressor impacting crop production.

Purpose of the Study:

• To investigate the impact of ground-level ozone on nitrogen (N) fertilizer use efficiency in wheat.
• To quantify ozone's effects on N efficiency for grain protein (NEp) and grain yield (NEy).

Main Methods:

• Analysis of a large dataset from 21 experiments (70 treatments) using data mining.
• Detailed analysis of a subset of 7 experiments (22 treatments) with stomatal ozone flux data.
• Examination of N, K, and P content in wheat plant fractions and grain.

Main Results:

• Ozone significantly reduced both NEp and NEy across datasets.
• Ozone impaired the translocation of N from vegetative parts to grain.
• Fertilizer efficiency for K and P was also negatively affected by ozone.

Conclusions:

• Ozone diminishes the effectiveness of N fertilizer, reducing grain yield and protein.
• Reduced N fertilizer efficiency due to ozone increases the risk of N losses (nitrate leaching, N2O emissions).
• Societal choices involve either accepting increased N pollution or reducing fertilization and accepting yield losses under elevated ozone.