Successful cultivation of crops with the finest nutritional properties is an issue of paramount importance in the agricultural and health fields and consequently determinant for a Sustainable Development.

Chlorosis is a plant disorder characterized by the yellowing of the leaves and occurs due to the absence of chlorophyll pigment of plants. The causes that may interfere in the production of chlorophyll are various and include nutrient deficiencies. Iron (Fe) is one of the nutrients most commonly associated with a poor production of chlorophyll and Iron Deficiency Chlorosis (IDC) is considered a serious environmental problem affecting the growth of several crops in the world. Soil or foliar application of synthetic Fe-chelates is one of the most common measures to correct IDC. The limited number of distinct Fe chelates that are used as fertilizers calls for the identification of new ligands capable of producing Fe-chelates with properties that allow more efficient pathways for root uptake, root to shoot translocation and maintenance of metal homeostasis.

First studies pointed out the potential of 3-hydroxy-4-pyridinone Fe-chelates’ family as new IDC correctors and two promising compounds have been identified: [Fe(mpp)3] and [Fe(dmpp)3], in hydroponically grown plants. Soybean treated with these chelates became healthier and accumulated more Fe than those treated with the commercial fertilizer. Studies in soil confirmed the potential of [Fe(mpp)3].

We are currently working on a project (NanoFertil) to overcome the drawbacks of currently used products, using nanotechnology to develop smart delivery systems, by considering the design of new and more efficient nanofertilizers, with lower environmental impact.


Foliar application of 3-hydroxy-4-pyridinone Fe-chelate [Fe(mpp)3] induces responses at the root level amending iron deficiency chlorosis in soybean. Santos, C. S., Rodrigues, E., Ferreira, S., Moniz, T., Leite, A., Carvalho, S. M. P., Vasconcelos, M. W. and Rangel, M., Physiologia Plantarum, 2021, 1-11; https://doi.org/10.1111/ppl.13367

A combined physiological and biophysical approach to understand the ligand-dependent efficiency of 3-hydroxy-4-pyridinone Fe-chelates. Santos, C. S., Leite, A., Vinhas, S., Ferreira, S., Moniz, T., Vasconcelos, M. W. and Rangel, M., Plant Direct, 2020, 4, e00256; https://doi.org/10.1002/pld3.256

Effect of tris(3-hydroxy-4-pyridinonate) iron(III) complexes on iron uptake and storage in soybean (Glycine max L.). Santos, C.S., Carvalho, S.M.P., Leite, A., Moniz, T., Roriz, M., Rangel, A.O.S.S., Rangel, M. and Vasconcelos, M.W., Plant Physiology and Biochemistry, 2016, 106, 91-100; http://dx.doi.org/10.1016/j.plaphy.2016.04.050