Establishment Of Callus Cultures Research Articles

Scopolin, a Biochemical Marker for Resistance to Thielaviopsis basicola in Callus and Crown‐Gall Tissue Cultures of Tobacco

AbstractScopolin concentration increased in tissue cultures where Thielaviopsis basicola growth ceased (primary and established callus cultures of the resistant tobacco cultivar Ky 170) while it decreased in tissue cultures where fungal growth persisted (primary and established callus cultures of the susceptible tobacco cultivar Ky 151 and crown‐gall cultures of Ky 170 and Ky 151). The concentration of chlorogenic acid, scopoletin, and two other unknown soluble phenols varied after inoculation and no, correlation with tissue culture resistance could be established. Incorporation of Agrobacterium tumefaciens T‐DNA in the genome of both cultivars induced a drastic reduction of scopolin in inoculated tissue cultures. T‐DNA incorporation had less, influence on uninoculated tissues. Scopolin at concentrations found in tissue cultures was not toxic to the fungus.

A genetic analysis of cell culture traits in tomato

Tomato genotypes superior in regenerating plants from protoplast and callus cultures were obtained by transferring regeneration capacity from Lycopersicon peruvianum into L. esculentum by classical breeding. The genetics of regeneration and callus growth have been studied in selfed and backcross progenies of a selected plant (MsK93) which has 25% L. peruvianum in its ancestry. Segregation data showed that the favourable cell culture traits of L. peruvianum are dominant. Regeneration capacity from established callus cultures was controlled by two dominant genes. Callus growth on primary expiants, callus growth of established cultures and shoot regeneration from explants had high heritabilities (0.47, 0.78, 0.87, respectively). Callus growth and regeneration capacity were not correlated within the populations studied.

Tissue culture and plant regeneration from immature embryo explants of Barley, Hordeum vulgare

Immature embryo explants taken 8 days after anthesis were used to establish callus cultures of spring barley. Two types of calli were observed. A soft, watery callus produced a limited number of shoots and a harder, more compact, yellowish callus gave rise to numerous green primordia and shoots. Gamborg's B5 basal medium supplemented with either 2,4-D (2,4-dichlorophenoxyacetic acid) or Cl3 POP (2,4,5-trichlorophenoxypropionic acid) was found to give good callus growth and shoot initiation. Media containing 2,4-D at 1.0 mg L(-1) or Cl3 POP at 5.0 mg L(-1) produced numerous cultures resulting in regeneration of plants. Plantlets developed roots on basal medium with Cl3 POP at 1.0 mg L(-1) or on auxin-free medium. Twenty genetically diverse genotypes were screened to determine if these techniques were suitable for a wide range of spring barley cultivars. Regeneration of plantlets was obtained for 19 of the 20 genotypes approximately 4 months after culture initiation. Lines differed in the ability to develop vigorously growing calli and in the ability of calli to develop large numbers of shoots and regenerated plantlets.

Variation in nicotine content of tobacco callus cultures

Plants ofNicotiana tabacum L. cv. Burley 21 which showed no difference in nicotine content were used to establish callus cultures. Cultures were initiated from different plants and from different leaves within each plant. The nicotine content of the calli was determined, and the results subjected to an analysis of variance. Differences between plants and differences within plants significantly affected the nicotine content of the cultures. The differences between plants were transmitted sexually and asexually, providing evidence that they are genetically determined. No such differences in nicotine content were found between the plants from which the cultures were established, indicating that nicotine production in vitro involves additional genes to those which are needed for nicotine production in the plant. The differences within plants were further investigated by establishing callus cultures from pith explants taken from different parts of the stem. Explants from apical pith tissue gave calli having far more nicotine and more roots than cultures derived from basal pith explants. This results may reflect the proximity of the apical pith explants to the site of auxin synthesis in the stem apex. Callus cultures derived from pith explants showed greater growth and nicotine production than those derived from leaf explants when the calli were induced on Murashige-Skoog medium containing α-naphthalene acetic acid. This result is in conflict with the widely held belief that explants from different parts of the plant give cultures with similar yields of species-specific compounds.

Alkaloid Production in Catharanthus roseus Cell Cultures X. Mitotoxic Effect of 3′,4′-Dehydrovinblastine

Summary Cells of established callus and suspension cultures derived from anther walls of periwinkle, Catharanthus roseus (L.) G. Don, responded to 0.2 x 10-3 M 3′,4′-dehydrovinblastine (dVBL) and vincristine with C-mitosis. Cells derived from protoplasts of periwinkle leaves and cultured for 3 weeks tolerated treatment with dVBL. The frequency of C-mitosis increased significantly as, over several weeks, protoplast derivatives continued to multiply and became callus cells, and in the presence of 5 x 10-3 M dVBL. The effect of vincristine was similar to that of dVBL. Vindoline and catharanthine, monomeric moieties of dVBL, did not exert mitotoxicity.

In Vitro Tissue Culture of Selected Legumes and Plant Regeneration from Callus Cultures of Red Clover1

A synthetic, chemically defined medium was developed for the initiation and growth of cell and tissue cultures of red clover (Trifolium pratense L.). The medium is broadly supportive and suitable for the culture of other legume species, including alfalfa (Medicago sativa L.), soybeans (Glycine max L.) and jack bean (Canavalia ensiformis L). Cultural variables for red clover were defined, and it is now possible to routinely establish callus cultures of red clover from reproductive and vegetative explant tissues of both mature and immature plants. Cell suspension cultures with rapid cell division rates have been established from calli by adapting the new medium to liquid culture. Organogenesis was induced in callus cultures, and the recovery of whole plants regenerated from callus has been achieved with the cultivars ‘Altaswede’, ‘Arlington’, ‘Kenstar’, ‘Redman’ and ‘Tensas’, but they did not respond equally well. Regenerated plants have been grown to maturity and were fertile. 3‐Aminopyridine was evaluated and found to possess growth‐modifying properties. It is now possible to investigate the use of tissue and cell culture techniques in red clover breeding programs.

Callus formation and differentiation in tissue cultures of normal and cytoplasmic male sterile sorghum, pepper, sunflower, and tobacco.

The primary goal of this study was to establish callus cultures of selected plant taxa containing both normal (N) and cytoplasmic male-sterile (CMS) lines. A secondary goal was to attempt to differentiate the calli into whole flowering plants. Undifferentiated and organ differentiated calli were produced in specific lines of N and CMS sorghum, pepper, sunflower, and tobacco. Calli from both N and CMS lines of a given species developed similarly and grew well. Even though whole flowering plants have not yet been produced from any of the lines, this approach allows for good production of callus for studies dealing with CMS.

THE FINE STRUCTURE OF WALL MODIFICATIONS AND ASSOCIATED STRUCTURES IN CALLUS TISSUE OF ANDROGRAPHIS PANICULATA NEES.

SummaryIn established callus cultures of Andrographis paniculata grown on a solidified nutrient medium, numerous spherical multivesiculate bodies, c. 0.6–3 μ in diameter, are visible. These usually contain membrane‐bounded vesicles and tubules of up to 0.2 μ diameter enclosed within one to several membranous lamellae, but myelin‐like forms also oeeur. The origin of sueh multivesiculate bodies is uncertain but the Golgi apparatus or endoplasmie reticulum may be implicated. The multivesiculate bodies apparently f'use to the cell wall to form lomasomes and these organelles deposit their membranous contents into the wall and give rise to membranous wall bodies. These bodies eontain a plethora of membrane‐bounded vesicles, or membrane segments which may be isolated or associated in myelin‐like configurations. The vesicles probably contain precursor materials utilized in the synthesis of the fibrillar material in which the membranous inclusions in the wall are embedded. Associated with the membranous wall bodies, numerous wall invaginations develop in seneseing tissue and divide the cells into progressively smaller compartments. The latter eventually become almost completely occluded, apparently due to the secretion of fibrillar material into their lumens by multivesiculate bodies and membranous wall bodies.