title: Stress-induced microspore embryogenesis in tobacco: an optimized system for molecular studies.
abstract: Specific stress treatments applied to isolated tobacco (Nicotiana tabacum L.) microspores efficiently induced haploid embryo formation in vitro. A heat shock at 33 or 37°C in the presence of sugar, as well as sucrose-starvation at 25°C, resulted in the formation of embryogenic microspores. A combination of both treatments had an additive effect. Under optimal induction conditions all viable microspores in the culture were embryogenic and developed subsequently into pollen embryos by culture at 25°C in a sugar-containing medium, with induction frequencies of more than 70% with respect to the initial microspore population. A high fraction of the early pollen embryos continued their development in vitro, giving rise to haploid plants. In contrast to other available systems for microspore/pollen embryogenesis, the new protocol allows the production of homogeneous populations of embryogenic microspores and early globular embryos in large-scale cultures, without any purification step, and is therefore well suited for biochemical and molecular work.
authors.affiliation: Vienna Biocenter, Institute of Microbiology and Genetics, University of Vienna, Dr. Bohr-Gasse 9, A-1030, Vienna, Austraia.
authors.forename: A
authors.initials: A
authors.lastname: Touraev
authors.forename: A
authors.initials: A
authors.lastname: Ilham
authors.forename: O
authors.initials: O
authors.lastname: Vicente
authors.forename: E
authors.initials: E
authors.lastname: Heberle-Bors