The Effect of Moderate Salt Stress on Leaf Anatomy in Hibiscus Cannabinus (Kenaf) and Its Relation to Leaf Area

Kenaf responded to salt stress in a manner that was typical of moderately salt tolerant non‐halophytes. Increase in leaf area was more sensitive to salinity than either leaf emergence rate or dry matter accumulation. Dry weight was reduced only above a threshold of approximately 37 mM NaCl while leaf area was already significantly reduced at this salt concentration. Measurement of epidermal cell cross sectional area and epidermal cell numbers showed that the salt induced reduction in leaf area was due primarily to smaller epidermal cell size. Epidermal cell numbers were also significantly reduced by salinity. Stomatal density increased with increasing salt stress and there was no effect on leaf thickness.