Abstract:

The types，distribution of trichomes on the leaf epidermis and the change of external morphorlogy during secreting process of the glandular trichomes on the leaf epidermis of Elsholtzia stauntonii，and thefluorescence intensity change during the process of secreting flavonoids Benth. were investigatedwere observed by means ofoptical microscopy，scanning electron microscope and fluorescence nucriscipe with Neu’s reagent staining. The results showed that：（1）E. stauntonii possesses glandular trichome and non-glandular trichome on the leaf epidermis and glandular trichome includes capitate and peltate glandular ones. ，（68.14 ± 0.84）μm in diameter，while a matured capitate one had a smaller and hemispherical-shaped head with a diameter of（17.57 ± 0.48）μm. Non-glandular trichome includes mastoid，ramose and tubular non- glandular trichome.（2）Trichomes were distributed both on the abaxial and adaxial leaf epidermis of E. stauntonii，the abaxial epidermis was with more glandular trichomes than the adaxial one，and the peltate glandular trichomes were mainly distributed on the abaxial surface and the capitates were distributed in both surfaces of the leaves. While non-glandular trichomes were distributed on both leaf surfaces and more were found around the veins，along the leaf margin and at the base of blade.（3）Secretions from the glandular trichomes stored in the space between cytoderm of secretory cells and head cuticle. The pressure to the head cuticle increased with the secretions accumulating，which led to the head cuticle depressed or ruptured and the secretions released，at last the glandular trichomes broke down.（4）Both peltate and capitate glandular trichomes can secrete flavonoids. With the glandular trichome development and maturation，the flavonoids were accumulated gradually in the head，and then released to the external space.A maturing peltate glandular trichome had a larger and shield-shaped head

Key words: Elsholtzia stauntonii, glandular trichomes, secretion, flavonoids