Embryological and Floral Effects Attributable to Deficiencies Following Crosses with X-Rayed Pollen of Lilium regale W

Abstract

Polyembryonic seeds of Lilium regale E. H. Wilson were induced by X irradiation of the pollen with 500 r. Mitotic analyses of 55 plants arising from the polyembryonic seeds disclosed that two sets of identical unattached twins were heterozygous for different gross deficiencies. Highly atypical flowers were produced by the deficient plants. Smaller deficiencies, beyond the limit of detection, undoubtedly were present in other sets of twins. Two sets of conjoined twins occurred. Increases or decreases in the number of floral parts were numerous; both members of a set of twins had similar flowers, indicating a common origin. It is concluded that X-ray induced deficiencies were responsible for cleavage during embryological development and the subsequent formation of atypical flowers.