Mónia A. R. MARTINS1, Leonard M. KIIRIKA1, Nicolas SCHAFFER2, Franklin GREGORY1, João A. P. COUTINHO2, Dibyendu MONDAL1
1Institute of Plant Genetics of the Polish Academy of Sciences, Strzeszy?ska 34, 60-479 Poznan, Poland
2CICECO – Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal
In the face of global population growth, the concept of sustainable agriculture and food security is becoming more and more important. Among the inefficient practices, the use of fertilizers in agriculture is a major concern, as only about 30% are utilized by crop plants, leading to unnecessary wastage in energy, water and arable land . Therefore, sustainable alternatives are being sought and among them, customized nanomaterials (NMs) stand out due to their potential in controlling nutrient release and stimulation of plant defenses against pathogens .
The nanoscale micronutrients currently under investigation consist of metals and metal oxides. Besides increasing nutrient absorption, nanoformulations of metal oxides such as copper oxide (CuO) and iron oxide (Fe2O3), are known for their effectiveness in mitigating disease damage . This ‘healing power’ is related to plant-based micronutrient nutrition, which emphasizes the sustainability of the process.
Micronutrients have been mostly applied to crops in salt or bulk hydroxide forms . Although this approach is somewhat effective on one hand, on the other hand, one must be cautious with the possible accumulation of metals in soils and sediments and leaching into watercourses. It is thus important to control the release of metal ions from NMs while exploring their particle dissolution to improve the fertilizer use efficiency .
The overall goal of this work is to investigate the release of metal ions from NMs in aqueous solutions containing ionic liquids (ILs) – a neoteric and attractive class of solvents for the controlled release of metal ions from NMs for agricultural applications. The release of CuO was investigated along with ILs made up of plant growth regulators-based biomolecules. ILs were characterized through NMR while nanoparticles were characterized by powder XRD, and TEM. Dissolution experiments were performed using dialysis membranes and metals were quantified using a TXRF spectrometer for ultra-trace element analysis. Aqueous solutions of ILs and CuO nanoparticles were then applied in tobacco plants (Necotiana tabacum) to determine the role of metal ion release profile in the presence of ILs. Phenotype-based screening method was employed to study root/above-ground related parameters. Findings of this study will foster development and understanding of various mechanisms of NMs in the field of plant nanotechnology.
This work was supported by the NANOPLANT project, which received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 856961.
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