Abstract
A plant steroid hormone, brassinolide, was found to induce parthenogenetic haploid seed generation when applied to the stigmas of the castrated flower buds. In the two species examined, Arabidopsis thaliana and Brassica juncea, haploid seeds were obtained which developed to stable haploid plants, but in the third species, Tradescantia paludosa, haploid seeds when germinated soon became haplo-diplo mixoploid and then diploid.
