Exchangeable sodium induced changes in yield, water relation and cation composition of fennel (Foeniculum vulgare Mill).

A pot experiment was conducted with the objectives to assess the adaptation potential of fennel crop grown at 10, 20, 25, 35 and 40 ESP (exchangeable sodium percentage) levels. Results showed that the rate of seed germination, plant growth including branching pattern, umbels per plant and 1000 test seed weight were adversely affected by sodic soils. Assuming that fifty percent reduction in seed yield and Na+/K+ ratio in leaf tissue as an index of alkali tolerance revealed that fennel was tolerant up to 25 ESP. The cell sap pH and EC reflected optimum osmoticum maintenance to withstand sodicity stress at this level and beyond this leaf water potential decreased (negatively) more to impede water uptake.