Micropropagation of Guarianthe skinneri (Bateman) Dressler & W. E. Higging in Temporary Immersion Bioreactors.

Guarianthe skinneri (Bateman) Dressler & W. E. Higgins is an orchid valued for its ornamental characteristics.

Micropropagation of Stevia (Stevia rebaudiana Bert.) in RITA.

Stevia rebaudiana Bert. is a plant that contains noncaloric sweeteners highly appreciated in the food industry. However, there is a high demand for propagules to establish commercial plantations, and the conventional reproduction types for this species are inefficient.

A differential response to chemical elicitors in Catharanthus roseus in vitro cultures.

The effects of methyl jasmonate, salicylic acid and ethylene on alkaloid accumulation in in vitro cell suspension, hairy roots and rootless shoot cultures of Catharanthus roseus were analyzed. Ajmalicine, but not catharanthine, accumulation was promoted by jasmonate and ethylene treatments in cell suspensions. In hairy roots, jasmonate induced the accumulation of both alkaloids, whereas ethylene only induced catharanthine accumulation.

Vindoline formation in shoot cultures of Catharanthus roseus is synchronously activated with morphogenesis through the last biosynthetic step.

Background And Aims: The Madagascar periwinkle (Catharanthus roseus) produces the monoterpenoid alkaloid vindoline, which requires a specialized cell organization present only in the aerial tissues. Vindoline content can be affected by photoperiod and this effect seems to be associated with the morphogenetic capacity of branches; this association formed the basis of the study reported here.

Methods: Vindoline-producing in vitro shoot cultures were exposed either to continuous light or a 16-h photoperiod regime.

Catharanthus roseus shoot cultures for the production of monoterpenoid indole alkaloids.

A protocol for the establishment of in vitro shoot cultures of Catharanthus roseus is described. Shoots can be maintained for more than 1 yr without evidence of tissue vitrification, disaggregation, or callus formation. Vindoline was the main alkaloid accumulated, reaching values similar to those found in leaves from field-grown plants, after a long period of culture.

Vindoline synthesis in in vitro shoot cultures of Catharanthus roseus.

Vindoline, the major alkaloid in cultures of Catharanthus roseus shoots, reached 2 mg g(-1) dry wt after 27 d in culture. Maximal vindoline accumulation coincided with maximum activities of deacetoxyvindoline 4-hydroxylase, deacetylvindoline acetyl-CoA acetyl transferase and tryptophan decarboxylase. Shoot exposure to jasmonate shortened the time required for the maximal vindoline accumulation to 14 d.