In vitro androgenesis and segregation distortion inBrassica napus L.: spontaneous versus colchicine-doubled lines.

A total of 750 plantlets were regenerated from 1,400 embryos produced through microspore cultures from one F1 plant of the cross 'Darmor-bzh' x 'Yudal'. Fifty-three percent of the regenerants were evaluated by flow cytometric analysis, which revealed that 31% were spontaneous diploid (SD), 63% were still haploid and the remaining 6% plants had other ploidy levels. Available segregation data (266 markers) produced on this androgenic progeny were used to study the interference between segregation distortion and the mode of chromosome doubling of androgenc lines. On the basis of the present results it is not possible to conclude that distortions are peculiar to one type of regenerated plant; only a difference in the intensity of the bias might be assumed.