Tissue culture root formation

The cell suspension cultures of this plant also showed good growth and formation of 2 (maximum level, 0.38 % as dw). Although the contents of 2 in tissue culture cells (both adventitious root and cell suspension cultures) were comparatively lower than those in the plants of Rhubarb (R. palmatum-6.06 % as dw R. officinale-X. % % as dw) (78), taking into account the rapid growth of the root and cell cultures, these cultures seemed to be useful for the production of 2. 

Micropropagation systems mentioned previously (Method I and Method II) require two different cultural steps, shoot multiplication and rooting. In the course of tissue culture studies of ipecac, adventitious shoot formation on cultured root had been incidentally found. Therefore, one step micropropagation system of ipecac was established through adventitious shoot formation on the cultured root [14]. 

In the meantime, the formation of the main alkaloids in C. ipecacuanha under a variety of conditions has been extensively investigated emetine (1) in callus cultures (49) and under the effects of L-tyrosine supplementation (5t)) emetine (1) and cephaeline (2) in Panamanian ipecac (57), in Nicaraguan ipecac (52), in regenerates obtained by clonal propagation (53,54), in tissue cultures (55) and under the effects of exogenous feeding of shikimic acid and L-phenylalanine (55), in cell suspension and excised root cultures (57), in adventitious root cultures (58), and in callus cultures (56,59) and the effects of age and electrokinetic potential (60) ipecoside (7) in the roots (61) and the effect oi Azotobacter, leaf mold, and farmyard manure on alkaloid content (62). In addition, micropropagation systems for C. ipecacuanha have been developed (63-65). 

Panax japonicus var. major is a wild dicotyledonous herb of Araliaceae which is maiidy distributed in southwest China and Himalayas areas . Its root has been used as an expectorant, antitussive and hemostatic in Chinese herbal medicine for a long time. And the main active constituents were thought as a wide range of saponins and sapogenins . Biotechnological alternative, i.e. cullus cultures, cell suspension cultures and hairy root cultures, has been adopted for in vitro saponin production. But, no study has been made for the tissue culture and secondary metabolism of this plant. This paper describes the hairy root culture and its saponin formation. 

Several authors have studied nicotine production (i.e., biosynthesis) in callus tissue cultures (Speake et al., 1964 Benveniste et al., 1966 Furuya et al.y 1966, 1971 Tabata et aL, 1968, 1971 Shiio and Ohta, 1973 and Heinze, 1975). The biosynthesis of nicotine is dependent upon the formation of organized tissue within the callus. Nodule-like structures similar to roots were observed in our laboratories using tobacco variety Maryland-872, which produces 96% of its alkaloids as nicotine. Shoot formation stimulated nicotine production in the callus, and nicotine may have been transported from the callus to the shoot. Nicotine production and tissue differentiation were dependent upon concentrations and types of growth regulators in the culture medium (Tables 4.3 and 4.4). The vegetative buds and leaves (shoots) contained about live times as much nicotine as callus without buds or leaves, which is in agreement with the results of Tabata et al (1968). 

Found in madder root Rubia tinctorum) as the glycoside, Ruberythric acid. Also found in R. iberica, R. cordifolia and in tissue cultures of Galium mollugo, Morinda citrifolia. Cinchona ledgeriana and C. pubescens. Bonds with calcifying tissues and has been used in studies of bone formation. Used in photometric detn. of B, Al, Ge, F , SO acid-base indicator (pH range 5.8-7.2 and 11.0-13.0). Orange or red needles or prisms (EtOH or by subl.). V. spar. sol. H2O. Mp 288-289°. Bp 430°. pi i 7.45 pK 2 11-80. Sublimes. 

Fig. 25.3 The pathways that can be taken in the development of plant tissue and cell cultures starting from a part of a plant (explant). The explant can via direct embryogenesis or oganogenesis form embryos or shoot and roots, respectively, which can be converted into plants. In another path, the explant can form a callus, which can then be used to form a suspension culture. In addition, indirect organogenesis or embryogenesis of the callus can lead to plant formation...

Cloning. Asexual propagation (cloning) of plants ordinarily occurs by virture of the ability of embryonic meristematic tissue to differentiate into roots and shoots. If isolated phloem cells or other more differentiated cells are cultured, the result is often the formation of a callus, a dedifferentiated mass of cells somewhat reminiscent of embryonic cells. Under proper conditions, e.g., in a coconut milk culture and in the presence of the correct auxin-to-cytokinin ratio, some carrot root phloem cells revert to embyronic cells and develop into intact plants.99 This experiment provided proof that the differentiated carrot phloem cells... 

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