Production of Haploid Plants From Anther Cultures and Secondary Embryoids of Winter Oilseed Rape, Brassica Napus Ssp. Oleifera

SUMMARY Following anther culture of a range of cultivars of winter oilseed rape, Brassica napus ssp. oleifera, approximately 15 to 70 % of the resulting embryoids developed directly into plants. The rest grew abnormally in culture, giving rise to abnormal plantlets which formed large numbers of secondary embryoids on their surfaces (up to 100 per abnormal plantlet). The secondary embryogenic plantlets were haploid, and the secondary embryogenic potential was maintained for over a year in culture without diminution. More than 70% of the secondary embryoids, and the plants regenerated from them, were haploid. These results are discussed in connection with the possibility of producing large numbers of haploid plants throughout the year for breeding purposes and for the production of novel disease resistant plants through genetic manipulation in culture.