Benefits of Biochar for Improving Ion Contents, Cell Membrane Permeability, Leaf Water Status and Yield of Rice Under Saline–Sodic Paddy Field Condition

Saline–sodic is one of the major conditions threatening crop production. Biochar application could alleviate the adverse impacts of saline–sodic stress in crops. But its effect on reducing Na + uptake in rice under saline–sodic paddy field condition remains unknown. This study evaluated the effect of biochar on ion contents, cell membrane permeability, leaf water status and yield of rice in saline–sodic paddy soil using a field experiment. The soil was amended with biochar at zero-biochar ( B 0), 33.75 t ha −1 ( B 1), 67.5 t ha −1 ( B 2), and 101.25 t ha −1 ( B 3), respectively. The results indicated that biochar addition significantly reduced Na + concentration and Na + /K + ratio, while it remarkably increased K + concentration of rice plant. Furthermore, biochar application significantly decreased the leaf-relative electrical leakage and increased leaf water status, plant height, and chlorophyll content index. The rice biomass production and harvested yield were significantly increased. Therefore, biochar application to saline–sodic paddy soil has benefits to alleviate saline–sodic stress and increase rice yield in saline–sodic paddy soil.