Regeneration of Diploid and Tetraploid Plants of Arabidopsis Thaliana via Callus

Different explants from diploid and tetraploid plants of Arabidopsis thaliana ecotype Wilna were cultured in vitro on the same medium in the same conditions. The mode and capacity for regeneration and the ploidy level of regenerants were examined in eight callus lines. The explant responses to in vitro conditions depended on the ploidy level of donor plants and on the type of explant. Callus derived from leaves of tetraploid plants showed the highest ability to regenerate. Histological investigation showed that plants regenerated mostly through organogenesis and occasionally through embryogenesis. Somatic embryos were observed more frequently in callus derived from tetraploid plants. Regenerated plants were diploids, triploids and tetraploids. The majority of regenerated plants from callus of diploid origin were diploid, but diploids were also observed quite frequently among regenerants from callus of tetraploid origin.