Specific programme: Joint Programming Initiative in “Sustainable Crop Production” funded through SusCrop - ERA-NET and AEI “Proyectos de Cooperación Internacional” (Proyecto PCI2020-120685-2, financiado por MCIN/AEI/10.13039/501100011033 y por la Unión Europea “NextGenerationEU”/PRTR).

APCIN code: PCI2020-120685-2

UPV/EHU Partner Status: Beneficiary

UPV/EHU PI: Begoña González

Project start: 01/04/2021
Project end:   31/07/2024
 

Brief description: Agrosystems in industrialized countries confront important challenges: they need to meet the increasing food demand, and at the same time they are requested to minimize negative environmental impact. The widespread use of synthetic nitrogen (N) fertilizers has promoted the productivity and profit in agricultural plant production. However, due to the low nitrogen use efficiency (NUE) of crop plants, the intensive use of N fertilizers entails losses from the plant-soil system via nitrate leaching and N gas emissions, leading to soil, water and atmosphere pollution.

The primary aim of the CATCH-BNI project is to improve the management of crop rotations, N fertilization and N cycling in agro-ecosystems by modulating nitrification and denitrification to contribute to a sustainable and environment-friendly agriculture. The nitrification processes operated by soil bacteria and archaea leads to the rapid conversion of ammonium into nitrate, which is prone to losses that subsequently pollute the environment. Nitrification is also associated with the emission of reactive nitrogen, mainly as nitrous oxide (N2O), which shows a potent global warming potential. Whereas the chemical inhibition of nitrification has emerged as a tool to limit nitrogen losses during last three decades, only more recently several plant species were lately shown to display nitrification inhibiting activity, mostly through release of organic compounds by root exudates. These compounds are named Biological Nitrification Inhibitors (BNIs). The characterization and use of BNIs allow the transfer and development of the nitrification inhibitorbased strategies to organic production and farming systems. Thus, BNI use represents a low-cost alternative to the application of chemical inhibitors.Moreover, tissues from certain plant species accumulating compounds with BNI activitiy during their development have shown the potential to reduce the nitrification activity. Thus, the use of catch crops as green manure when are incorporated into soil before sowing the target crop is hypothesized to improve soil fertility and concomitantly provide compounds that slow down nitrification process. This is the case for glucosinolate-containing plant tissues from mustard or rapeseed (Brassicaceae family), for which a greater accumulation of ammonium was observed in soils amended with their tissues.

The CATCH-BNI project aims to investigate the incorporation of catch crops with BNI potential into crop rotations as a mitigation strategy to slow down nitrification processes as well as to increase soil N pools for the subsequent target crop. Our main objective is to design innovative approaches enabling slower and controlled conversion of ammonium into nitrate in soils for optimal nutrition of target crops. For this, we aim at: 1) identifying catch crop plant species and cultivars with BNI activities in root exudates, and root and shoot tissues; 2) understanding how efficiently the N cycling is impacted by the use of BNI-producing catch crops and how the target crops perform (yield and NUE); 3) determining the best options and modalities to stabilize organic fertilizers with plant material with BNI activity; and 4) validating in real-field conditions the proposed innovations