Reducing N Fertilization without Yield Penalties in Maize

MARCH 12th, 2012

Conventional management of agricultural production has often depleted soil quality and decreased soil health. Depleted soils can further reduce the provision of essential ecosystem services for crop production and local environments, impacting yields and water use efficiency. The combination of intensive tillage and high nitrogen (N) fertilization also increases the mineralisation of soil organic carbon (SOC), a process that releases CO₂ emissions and exacerbates the contribution of agricultural soils to Greenhouse Gas concentrations (GHGs) in the atmosphere[1]. Finding solutions that work within farmer economics to maintain crop production while mitigating environmental and climate impacts is an essential step toward a more sustainable world.

The study (https://doi.org/10.3390/agronomy11030407) was designed to evaluate the possibility to reduce synthetic N fertilization in the cultivation of corn (Zea mays L.). The trial was conducted at CERZOO research center (Piacenza, Northern Italy), under real world field conditions using existing agricultural soil, in 200 m² plots, randomized to minimize the influence of any potential soil differences upon the final results. Three levels of fertilization were tested: 230 kg (100%), 160 kg (-30%) and 0 kg of synthetic N were applied in different plots after a common fertilization with 50 kg of equivalent efficient N from cattle slurry, with COCUS MAIZE COMPACT and without (Control). The roots were measured at anthesis and the crop cycle N₂O emissions were measured for the entire crop cycle year (April 2019 - April 2020). A comparison analysis was conducted for root structure, crop yield, and soil N₂O emissions between the control plots using fertilization at 100% synthetic N and the COCUS MAIZE COMPACT plots using -30% less synthetic N. Field data demonstrated a significant increase for the SOP treated plants in the very fine root hairs and the fine root length, both of which improve the efficiency of water uptake and plant nutrient cycling. Yield remained stable for both plots, Control and SOP (approximately 14 tons of grain per hectare), while N₂O emissions decreased by -23% per unit of production in the SOP treated plots.

The possibility to reduce synthetic N fertilization while maintaining crop yields would represent a step forward toward both environmental sustainability, human health, and overall food security under increasing risks from climate change.

The crucial link between the UN Sustainable Development Goals (SDGs) and agricultural production is based upon the efficient use of nitrogen in cereal production systems [2]. The European Commission (EU) has also recognised this crucial link, and has set ambitious goals for reducing synthetic fertilizer usage by -20% at the field level by 2030 [3]. The primary reasons for these regulatory guidelines are the significant impacts upon the environment and human health from the inefficient use synthetic fertilization in agricultural production [4]. Most importantly, it is generally known that the excess use of synthtetic N fertilization does not necessarily lead to increased crop yields, but can instead lead to high N losses in surface- and groundwater bodies causing negative water quality impacts, in addition to increased atmospheric GHGs emissions via N₂O cycling [5]. Products with the SOP Inside Technology demonstrate the ability to improve the environmental footprint of agricultural operations and to reduce the risks associated with climate change for staple crop production.

By establishing a commercial and scientific basis for maintaining current crop production levels with reduced need for synthetic fertilization, SOP products support the UN SDG framework for a more sustainable world and can be recognized by producers and their supply chains for SDG6 (Water Quality), SDG11 (Sustainable Cities), SDG12 (Responsible Production), SDG13 (Climate Action), and SDG15 (Life on land). The COCUS MAIZE COMPACT application has been certified according to ISO standards and the ISO warrants the recognition of alignment with the UN SDG goals with this SOP application in commercial use.