The development of haploid embryoids from anther cultures of Atropa belladonna L.

Development of haploid embryoids from the microspores of Atropa belladonna occurs with relatively high frequency when anthers are excised from buds in which the petals are shorter than the sepals (at this stage microspores are predominantly uninucleate) and cultured on a medium containing iron as the ferric salt of ethylenediamine-di-O-hydroxyphenylacetic acid (FeEDDHA). Additions of combinations of kinetin, auxin and casamino-acids to the culture medium induce callusing in both haploid and diploid tissues, lead to the origin of embryoids from somatic tissues of the anther and should be avoided. Simple techniques for the maintenance of haploid clones are described.Stages in early embryogenesis in the pollen grains have been observed and these indicate that embryogenesis is most frequently initiated by an equal division in the uninucleate spore. The frequency of grains showing embryoid formation is very low and it is estimated that plantlets are formed from up to 50% of these grains.