Structural, developmental and functional analyses of leaf salt glands of mangrove recretohalophyte Aegiceras corniculatum.

This article focuses on the structural, developmental, degenerative, and functional characteristics of salt glands and their salt secretion mechanisms in the mangrove plant *Aegiceras corniculatum*. The study found that salt glands develop early from a single epidermal cell, increasing in size and secretory cell number as leaves mature, while gland density decreases and degeneration progresses through defined stages. Salt secretion rates, particularly of sodium (Na⁺) and chloride (Cl⁻), increased with higher external NaCl concentrations, peaking at 400 mM, with the adaxial (upper) leaf epidermis exhibiting greater salt-secreting capacity than the abaxial (lower) epidermis. Gene expression analyses indicated that Na⁺/H⁺ antiporters, H⁺-ATPases, K⁺ channels, and Cl⁻ channels are involved in regulating salt gland development and salt secretion. These findings enhance understanding of salt tolerance mechanisms in *A. corniculatum* and provide a basis for further molecular-level research on mangrove salt glands.