NO , PO and SO deprivation reduced LKT1-mediated low-affinity K uptake and SKOR-mediated K translocation in tomato and Arabidopsis plants.

Regulation of essential macronutrients acquisition by plants in response to their availability is a key process for plant adaptation to changing environments. Here we show in tomato and Arabidopsis plants that when they are subjected to NO , PO and SO deprivation, low-affinity K uptake and K translocation to the shoot are reduced. In parallel, these nutritional deficiencies produce reductions in the messenger levels of the genes encoding the main systems for low-affinity K uptake and K translocation, i.

High Ca(2+) reverts the repression of high-affinity K(+) uptake produced by Na(+) in Solanum lycopersycum L. (var. microtom) plants.

Potassium (K(+)) is an essential nutrient for plants which is acquired by plant roots through the operation of specific transport systems. Abiotic stress conditions such as salinity impair K(+) nutrition because, in addition to other effects, high salt concentrations in the solution bathing the roots inhibit K(+) uptake systems. This detrimental effect of salinity is exacerbated when external K(+) is very low and the only system capable of mediating K(+) uptake is one with high-affinity for K(+), as that mediated by transporters of the HAK5 type.