Haploid plants regenerated from androgenic cell cultures of Digitalis lanata

Androgenic callus was obtained from cold treated anthers and pollen of Digi talis lanata. The callus was mixoploid and contained haploid, diploid and t etraploid cells as shown by impulse cytophotometry. Haploid cell lines were selected by colony cloning. They were unstable and selection had to be rep eated every 1-2 months. Mixoploid shoot cultures were derived from embryoge nic haploid cell lines via somatic embryos. Haploid shoots were selected by explanting shoot tips. The shoots showed wide variability in cardenolide c ontent and profile. Rooting of the haploid shoots resulted in haploid plant s. These plants were smaller in size than diploid plants. Often the flowers were morphologically abnormal and showed male sterility due to crippled an thers.