Haploid plants from pollen grains.

A method is presented by which hundreds of haploid plants of various species of Nicotiana can be raised from pollen grains. Stamens should be excised when pollen grains have been individualized, but are still uninucleate and free of starch. When grown in vitro on a relatively simple medium, some pollen grains proliferate into embryo-liké, structures which develop in stages similar to those of zygotic embryos. The plantlets mature and flower profusely, but do not set seed.