The main roots and leaves of Panax ginseng C.A. Meyer were studied by a light, scanning and transmission electron microscopy pertaining to their ages, grades, and cultivars. The transverse sections of main roots showed that the most of tissues were co...
The main roots and leaves of Panax ginseng C.A. Meyer were studied by a light, scanning and transmission electron microscopy pertaining to their ages, grades, and cultivars. The transverse sections of main roots showed that the most of tissues were composed of different number of cells in pith and cortex region depending upon their ages. However, periderm, the outermost tissue of root was usually stacked with five layers of cork cells in all age. Pericycle zone of the different aged samples was commonly composed of five to seven cell layers.
Hand free sections stained with nile blue of 1, 2, 3, 4, 5, and 6 year old roots were observed to identify the secretory ducts. Secretory ducts have some pattern; 1-year old root has scattered form, 2-year old root has one, 3-year old root has two, 4-year old one has three, 5-year old one has four, and 6-year old one has five resin duct layers on each cortical regions.
Three groups of ginseng roots, Grade 1, 2, and 3 are usually distinguished each other by external features, such as shape, and weight of roots. The major factor influencing on grades of ginseng roots is the number of cell layers in cortex and pith. In the cortex of ginseng root, the more cell layers are, the higher the level of grade is. However, in the pith of ginseng root, the less cell layers are, the lower the level of grade is.
The most distinct difference between rusty roots and normal roots is that the former has reddish spots at its periderm and finally lose partially or totally its periderm cells. The healthy periderm of root is usually consisted of 5 to 8 cork cell layers. However, the periderm of lightly and medium damaged root has 15 to 20 cork cell layers because the cork cambium actively generate additional cell layers toward the outside. To replace detached periderm in heavily damaged root, the cortical cells are immediately transformed into the periderm-like cells.
Estimated quantity of iron by Energy Dispersive X-ray(EDX) in rusty roots show that irons are positively present at reddish spots in lightly damaged root, But not in any cells of the healthy root periderm cells. To determine the difference of five ginseng cultivars, we examined the morphological characteristics of leaves of five representative ginseng cultivars.
The most popular types of ginseng are five cultivars; Go-Poong, Geum-Poong, Sun-Poong, Yun-Poong, and Chun-Poong. To investigate the difference of leaf structure between five cultivars of ginseng, we examined the several morphological aspects such as size of epidermis cell, thickness of cuticle layer, number of stomata in leaves by the light, scanning and transmission electron microscope.
In thickness of cuticle layer and cell wall of each cutivars, Yun-Poong was thinner than those of the others. In distribution of cuticle ridges at periderm, Geum-Poong, Sun-Poong, Yun-Poong had a few density at their periderms. Yun-Poong had the biggest number of stomata in abaxial leaves, however, Chun-Poong had poor in number of stomata. This result suggest that the former has an advantage to process the photosynthesis than other cultivars, while it has a disadvantage under the strong sunlight conditions.