Micrographs of in planta and in vitro isolated AVIs of the adaxial cells of the inner petal region of lisianthus flowers. A. Light microscopy section of an isolated AVI stained with Toluidine Blue, showing the uneven distribution of the internal structure. B. TEM image of an isolated AVI, showing the thread-like structure. C. TEM image of an AVI-containing cell, showing dense inner (white arrowhead) and loose outer thread structures of the AVI in the central vacuole (V). CW, cell wall; PM, plasmodesmata. D. Higher magnification image of the transition part between dense and loose AVI thread structure of an AVI.