Salinity induced potassium deficiency in maize plants

Maize (Zea mays L.) plants were grown in 1/2 Hoagland nutrient solutions to study the effect of two K+ levels (0.1 and 1 mmol/L) combined with low (0.1 mmol/L) and high NaCl salinity (100 mmol/L) on K+ uptake and translocation. Net uptake rates of K+ were determined by disappearance in the medium and by plant content. Salinity significantly decreased shoot growth when the level of K+ in the solution was 0.1 mmol/L, probably due to a salinity-induced K+ deficiency NaCl reduced Kt net uptake rates and to a greater extent Kf translocation from root to shoot, which resulted in a lower K+ shoot content and a higher Kf root content. The inhibitory effect of salinity on K+ translocation was stronger with low K+ concentration in the nutrient solution. Net uptake of K+ was dependent on K+ concentration in the root medium and on K+ status of the root.