Cultures Of Single Cell Origin

Cultures can be initiated from single plant cells, but only when special techniques are employed. Frequently these comprise passing suspension-cultured cells through a filter which removes coarse cell aggregates and allows only single cells and very small cell clusters to pass through. Small groups of cells are then assumed to have originated from single cells. The suspension obtained is usually plated onto (or incorporated into) a solidified medium in Petri dishes at a sufficient density to...

References

ABO EL-NIL M.M. & HILDEBRANDT A.C. 1976 Cell wall regeneration and colony formation from isolated single geranium protoplasts in microculture. Can. J. Bot. 54, 1530-1534. ABO EL-NIL M.M. & ZETTLER E.W. 1976 Callus initiation and organ differentiation from shoot tip cultures of Colocasia esculenta (Taro). Plant Sci. Lett. 6, 401-408. ADAMS A.N. 1972 An improved medium for strawberry meristem culture. J. Hortic. Sci. 47, 263-264. AHEE J., ARTHUIS P., CAS G., DUVAL Y., GUENIN G., HANOWER J.,...

Inorganic Medium Components

Plant tissues and organs are grown in vitro on artificial media, which supply the nutrients necessary for growth. The success of plant tissue culture as a means of plant propagation is greatly influenced by the nature of the culture medium used. For healthy and vigorous growth, intact plants need to take up from the soil relatively large amounts of some inorganic elements (the so-called major plant nutrients) ions of nitrogen (N), potassium (K), calcium (Ca), phosphorus (P), magnesium (Mg) and...

Potassium

Potassium is the major cation (positive ion) within plants reaching in the cytoplasm and chloroplasts concentrations of 100 - 200 mM. The biphasic uptake kinetics suggest two uptake systems a high-affinity and a low-affinity one. K+ is not metabolised. It contributes significantly to the osmotic potential of cells. K+ counterbalances the negative charge of inorganic and organic anions. It functions in cell extension through the regulation of turgor, it has a major role in stomatal movements and...

The propagation of orchids

Morel (1960) noticed that when protocorms of Cymbidium were divided new protocorms were formed from the pieces, whereas if they were not divided, original and regenerated protocorms developed into new plantlets. Morel (1960, 1964) suggested that meristem or shoot tip explants could be used to establish cultures for the clonal propagation of orchids, providing thereby the basis of the method which is now used for many orchid genera. Rates of propagation are improved through the use of slightly...

H H

Fig. 3.1 The structures of allantoin and allantoic acid. Most media contain more nitrate than ammonium ions, but as plant tissue culture media are usually not deliberately buffered, the adopted concentrations of ammonium and nitrate ions have probably been more due to practical pH control, than to the requirement of the plant tissues for one form of nitrogen or another (see chapter 4). Uptake of nitrate only takes place effectively in an acid pH, but is accompanied by extrusion of anions from...

Early Use In Plant Tissue Culture Media

At the time of the early plant tissue culture experiments, uncertainty still existed over the nature of the essential microelements. Many tissues were undoubtedly grown successfully because they were cultured on media prepared from impure chemicals (see below) or solidified with agar, which acted as a micronutrient source. In the first instance, the advantage of adding various micronutrients to culture media was mainly evaluated by the capability of individual elements to improve the growth of...

Aluminium And Nickel

Several workers, following Heller (1953), have included aluminium and nickel in their micronutrient formulations. However, the general benefit of adding the former metal does not seem to have been adequately demonstrated. It was believed that in most plants Ni2+ is not absolutely required for normal growth and development (Mishra and Kar, 1975). However, more recently, it has been found by careful experimentation that nickel is essential (Gerendas et al, 1999). The ion is a component of urease...

The Production Of Bulbils And Cormlets

Species that naturally produce bulbs can be induced to form small bulbs (bulbils or bulblets) in culture. Bulbils can be produced from axillary buds, but frequently they are formed from adventitious buds developed on pieces of leaf, on inflorescence stalks, or on ovaries, and particularly on detached pieces of bulb scale. Both axillary and adventitious shoots and bulbils are formed on bulb scale pieces in vitro. Strong dominance of the main shoot apex often prevents the formation of axillary...

Related To Medical Dhpt

1,3 with observations on animal tissues, Weinstein et al., (1951) suggested that toxicity arose through competition between EDTA and enzymes (and other physiologically-active complexes) in the plant, for metals essential to their activity. This will occur if the avidity of the chelating agent is greater than the metal binding capacity of proteins on the surface of cells (Albert, 1958). Toxicity can also occur in in vitro cultures. Legrand (1975) found that an optimum rate of adventitious shoot...

Protocorm formation in orchids

The seeds of orchids (like those of some other saprophytic or semi-parasitic plants) contain a small embryo of only about 0.1 mm diameter, without any associated endosperm storage tissue. Upon germination, the embryo enlarges to form a small, corm-like structure, called a protocorm, which possesses a quiescent shoot and root meristem at opposite poles. In nature, a protocorm becomes green and accumulates carbohydrate reserves through photosynthesis. Only when it has grown and has sufficient...

Tissue maceration or fragmentation

The capacity of young fern tissue to regenerate adventitious shoots can be very high. Fern prothallus tissue the gametophyte generation produced from germinating spores has a high capacity for regeneration a new prothallus can usually be grown from small isolated pieces of tissue Whittier and Steeves, 1962 , or even from single cells produced by maceration Miller J.H., 1968 De Fossard, 1976 Knauss, 1976 . Plants can also be regenerated from homogenised sporophyte tissue of some fern genera, and...

Culture Of Unorganised Cells

Callus And Suspension Culture

Callus is a coherent and amorphous tissue, formed when plant cells multiply in a disorganised way. It is often induced in or upon parts of an intact plant by wounding, by the presence of insects or microorganisms, or as a result of stress. Callus can be initiated in vitro by placing small pieces of the whole plant explants onto a growth-supporting medium under sterile conditions. Under the stimulus of endogenous growth regulators or growth regulating chemicals added to the medium, the...

Explant

The discovery that roots could be grown apart from shoot tissue was one of the first significant developments of modern tissue culture science. Root culture initially attracted a great deal of attention from research workers and the roots of many different species of plants were cultured successfully see the comprehensive reviews of Street, 1954, 1957, 1969 and Butcher and Street, 1964 . Plants fall generally into three categories with regard to the ease with which their roots can be cultured....

Ck

Fig. 3.5 Copper chelated with amino acid, glycine. Iron chelates. A key property of iron is its capacity to be oxidized easily from the ferrous Fe II to the ferric Fe III state, and for ferric compounds to be readily reduced back to the ferrous form. In plants, iron is primarily used in the chloroplasts, mitochondria and peroxisomes of plants for effecting oxidation reduction redox reactions. The element is required for the formation of amino laevulinic acid and protoporphyrinogen which are...

Micrografting

The transfer of small shoot apices onto rootstocks termed micrografting , can be carried out in vivo or in vitro. Navarro 1988 lists four uses which have been found for the technique Obtaining plants free from specific virus and virus-like diseases A method for separating virus and virus-like organisms in mixed infections For studying graft incompatibility between scions and rootstocks, and the histological and physiological aspects of grafting A minimum risk method for importing plant material...