MicroFert · Novel Release-on-demand micronutrient fertilisers for crops

Novel Release-on-demand micronutrient fertilisers for crops

In many important agricultural crops successful fertilisation with micronutrients can lead to substantial increases in resistance to diseases, significant increases in the marketable yield, and improved nutritional quality of food and feed. However, the plant availability of supplied micronutrient fertilisers is in many cases too low due to the high reactivity of fertilisers under unfavourable soil conditions. New and more efficient micronutrient fertilisers may therefore make a substantial contribution to improving production systems for important agricultural crops Recently novel concepts for designing ‘slow release’ or ‘controlled release’ fertilisers have been adopted which try to extend their time of availability in the soil in different ways. This project introduces the release-on-demand concept in which the plants themselves trigger the release of nutrients from nanoparticles at the time in their growth cycle that they need them. Layered Double Hydroxides (LDHs) used in development of drug delivery systems are currently being developed in the host institution and are seen as interesting candidates for the controlled release of nutrients including trace nutrients in the formulation of new fertilisers. LDHs consist of alternating layers of positively charged metal hydroxides and interlayers of charge compensating anions so they can include both divalent and trivalent metal cations, e.g. Mg2+, Fe3+, Al3+, Cu2+, Zn2+, Mn2+ and many different interlayer anions, e.g. carbonate, nitrate, sulphate, phosphate, selenate and molybdate. The nutrient release is expected to be dependent on rhizosphere acidification occurring via root excretion of protons, low molecular organic acids and/or CO2. In addition, root derived carboxylates may complex metal cations and facilitate their release from the LDH. Moreover, there is a strong interest in their patenting and utilisation, ensuring a high likelihood for their future commercialisation should the results of this study be promising. The overall objective of this MC project is to evaluate the potential of synthesised LDHs as release-on-demand micronutrient fertilisers, mainly focusing on Zn, Mn and Cu, but also their interactions with N under a range of soil conditions and growing conditions. The experiments conducted cover both highly controlled stability and nutrient release in solution and delivery to several important plant species under alternating soil conditions.

Data: CORDIS, © European Union