Interaction of ammonium nutrition with essential mineral cations

Abstract

Plant growth and development depends on sufficient nutrient availability in soils. Agricultural soils are generally nitrogen (N) deficient and thus, soils need to be supplemented with fertilizers. Ammonium (NH4 +) is a major inorganic N source. However, at high concentrations ammonium nutrition becomes a stress situation that inhibits plant growth. The cause of ammonium stress or toxicity is multi-factorial but the interaction with other nutrients is among the main determinants of plants sensitivity towards high NH4 + supply. In addition, NH4 + uptake and assimilation provokes the acidification of the cell external medium (apoplast/rhizosphere), which has a clear impact on nutrients availability. This review summarizes current knowledge, at both physiological and molecular level, of ammonium nutrition interaction with essential mineral elements absorbed as cations: macronutrients (K +, Ca 2+, Mg 2+) and micronutrients (Fe 2+/3+, Mn 2+, Cu +/2+, Zn 2+, Ni 2+). We hypothesize that considering these nutritional interactions, and soil pH, when formulating fertilizers may be key in order to boost the use of NH4 +-based fertilizers, which have less environmental impact compared to the nitrate-based ones. In addition, we are convinced that better understanding these interactions will help to identify novel targets with potential to improve crop productivity.

Manganese and phosphorus maize shoot concentrations are differently affected by nitrification inhibitor‐driven rhizosphere acidification

“…The two experiments carried out in this study showed that DMPP stabilized-NH 4 + decreased the overall plant shoot biomass by 10% in unlimed soil (Figures 2 and 5). The negative effect of sole NH 4 + -N nutrition in plants is welldocumented in the literature and is ascribed to several factors directly or indirectly linked to NH 4 + -N uptake, accumulation, and assimilation (Britto & Kronzucker, 2002;Coleto et al, 2023;Kong et al, 2022). For instance, such factors include acidification of the rhizosphere beyond critical levels for plant growth, increased strength of the root tissue as a carbon sink under NH 4 + -N nutrition due to enhanced synthesis of amino acids, and the adverse effect on the uptake of the other cationic nutrients (Kong et al, 2022).…”