Influence of saline water and nitrogen application on leaf nutrient concentrations and yield of sweet sorghum

Abstract

We evaluated the influence of the combinations of four N levels with three NaCl levels, applied through irrigation, on leaf N, P, K, Ca, Mg, and Na concentrations of sweet sorghum (Sorghum bicolor ssp. saccharatum), in two consecutive years of an experiment established on a Eutric Fluvisol in Alvalade-Sado region, equipped with a drip irrigation system ("Triple Linear Source"). The relationships between leaf nutrient concentrations and dry matter production (stems, leaves, and aerial biomass), and between N and NaCl levels and the leaf nutrient concentrations were also searched. It was nitrogen availability in soil that, more than salinity, affected nutrient uptake, with reflexes on the leaf concentrations and the yields. Leaf N concentration was the best indicator for predicting the stems production of sweet sorghum.