The genotypic responsiveness to androgenesis and the effect of two exposure times of cultured anthers to auxins (12 days and the entire period of culture) were studied in three lines of cauliflower (one spring ‐ and two winter‐types). The anthers of all genotypes responded to the protocol by producing embryos (0.2 ‐25.3%), 44.2% of which regenerated plantlets through organogenesis on a regulator‐free B5 medium containing 40 g/l of sucrose and 800mg/l of L‐glutamine. Embryo yield improvement, recently achieved on solid medium with the addition of 125mg/l silver nitrate, was not observed in liquid cultures. Mean frequencies of androgenic embryos, as affected by the duration of auxin supply to the culture, were always significantly higher (6.6‐ and 8.1‐fold.) in the‘12 days of exposure’treatment than in the‘entire period of culture’treatment. The resolution of the parameter‘embryo percentage’into its two components (% of responsive anthers and number of embryos per responsive anther) gave evidence of a highly significant increase in the percentage of responsive anthers, whereas the number of embryos per responsive anther did not change statistically. The percentage of embryos regenerating plants was not influenced by the duration of auxin supply during anther culture. Chromosome count analysis revealed a haploid/diploid/polyploid plant ratio of 6:79:15. Of the 78 androgenic plants (RO generation) grown in the field, only 14 were fertile and produced seeds. RAPD analysis showed that none of the seven polymorphic loci out of 23 analysed expressed polymorphism within the RI progenies of 11 anther culture‐derived lines.

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