Iron (Fe) is an essential nutrient for plant growth and development and for human nutrition. However, its deficiency constitutes a serious problem in the agricultural sector and the food of populations worldwide. This nutrient can be present in different oxidation states, which condition its bioavailability. In calcisols (calcareous soils), it can precipitate and present low availability, causing iron deficiency chlorosis (IDC) in plants – a condition that reduces crop quality. Although plants naturally access soil Fe through acidification–chelation or chelation mechanisms, Fe nutrition management strategies have been proposed for alkaline soils to maximize or enhance these mechanisms. In this review, we have summarized the main research on ferric nutrition in calcisols, highlighting advances in the use of grafting systems, intercropping systems, ferric fertilizers, new chelates, nanotechnology, and bioengineering, and the underlying mechanisms. The use of fertilizers, chelates, and nanotechnology allows the stabilization of Fe, promoting a constant, continuous, and bioavailable supply in the soil–plant system. Practices such as grafting, intercropping, and organic complexes promote microbiological and enzymatic activity, inducing favorable environments that improve Fe availability and absorption. Moreover, knowledge of the mechanisms of Fe absorption, transport, and assimilation has allowed the selection and manipulation of genetic resources robust enough to cope with calcisol soil environments. Iron deficiency has been addressed elsewhere; our review was focused on calcisol soil conditions, bringing together new knowledge from the different tools used to alleviate IDC and promote growth and crop production. This review demonstrates how efficient and sustainable the use of Fe can be in calcisol soils, and it provides an overview of several unresolved or unaddressed issues with the expectation of attracting interest in the development of a research program to seek to mitigate IDC and ultimately promote crop quality in calcareous soils.
Key words: grafting, intercropping systems, iron deficiency chlorosis, nanotechnology, novel chelates.
|
