ChileanJAR

In orderto establish an efficient method for artichoke (Cynara scolymus) micropropagation, tissue culture media reported in the literature for the establishment, proliferation, and rooting of this species were evaluated. The effect of extracting the meristems in september, october or november on survival and subsequent growth of the explants, was also tested. AII experiments were conducted at the Micropropagation Laboratory ofthe Faculty of Agronomy of the Catholic University of Valparaiso (Chile). Methods for meristem culture were those described elsewhere for other species. Results demonstrated that rooted plantlets can be obtained in 6 month, starting with apical meristems, 0.5 cm in length, exCised from basal shoots arising from 2- year-old field plants. Explanting meristems in september, october or november did not affect their survival in culture. nor was subsequent growth, contamination or rooting of the explants affected. The best medium for initiation of cultures was that described by Pecaut and Martin (INRA, no publicado). For shoot proliferation, media reported by Ancora and others (1981), and Pecaut and Martin (INRA, non published data) resulted equally adequated, with multiplication rates ranging from 6.0-6.9 after 8 weeks in culture. Rooting was not only affected by the rooting medium used, but also by the medium used during the proliferation phase, with the medium described by Pecaut and Martin being the best in promoting root formation. Rooting media containing NAA in concentrations ranging from 2-20 mg/L were the best for root formation. Endogenous contamination was the main problem detected for the micropropagation of this species, because it caused rapid explant deterioration and asevere decrease in the overall vigor of the plantlets.