In vitro-regenerated wetland sedge Eriophorum vaginatum L. is genetically stable

Eriophorum vaginatum L. is a promising species for phytostabilization, restoration, or creation of wetlands, because it can survive in cold, nutrient-poor, or metal-contaminated soils. However, its propagation on a large scale is problematic due to the infrequent production of viable seeds, seed dormancy, and the limitations of reproduction by rhizomes. A technique to rapidly and effectively produce large quantities of outplanting stock of this species was sought. Seeds of E. vaginatum were cultured on Murashige and Skoog (MS) medium supplemented with plant growth regulators at different concentrations. The highest regeneration rate was obtained on MS medium supplemented with 2.26 mu M 2,4-dichlorophenoxyacetic acid (2,4-D) and 2.32 mu M kinetin (KIN) for callus induction, and 17.76 mu M BA (6-benzylaminopurine) for shoot regeneration as well as when 2.26 mu M 2,4-D and 4.65 mu M KIN was added to the callus-induction medium, and 8.88 mu M or 17.76 mu M BA to the shoot-regeneration medium. The regenerated shoots were rooted on MS medium without growth regulators and acclimatized in a greenhouse. Genetic stability of the in vitro regenerants was determined using flow cytometry and random amplified polymorphic DNA. Cytometric analysis revealed that the nuclear DNA content was similar in all plant materials and amounted to about 0.8 pg/2C. The PCR amplification products were monomorphic in callus-derived plants and similar to plants grown in a field. Lack of genome size variation and polymorphism within the regenerants indicates that the detailed E. vaginatum micropropagation protocol allows the production of a large number of genetically stable plants.