Structural differences between vitrified and glaucous plantlets produced in vitro in Gypsophila paniculata were investigated by light, scanning and transmission electron microscopy.
It was observed that vitrified leaf had only sponge tissue, and no palisade tissue. Abnormally thick and broad leaves had both types of tissue but their size and intercellular space was large, compared with glaucous leaves.
Vitrified leaf showed larger stomata than glaucous one and the distinction between guard and subsidiary cells was not evident. The stomata of glaucous leaf issue were round shape, compared with one of greenhouse-grown leaf tissue. Comparison of stem tissue showed wrinkle but no stomata in glassiness, and normal stomata in glaucous stem. The wax rod were observed only on greenhouse-grown plants. The mesophyll cell of vitrified plantlet has poor in cytoplasm and fewer chloroplasts than that of glaucous leaves, and greatest part of cell volume was occupied by the vacuole. Starch accumulation in chloroplasts of vitrified plantlet cell was accomplished significantly, compared with cells of glaucous and greenhouse-grown plantlets, and osmiophilic globules were observed commonly in cells of vitrified and glaucous plantlets.
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