The present invention describes a novel plant hydroxysteroid dehydrogenase gene, (HSD) that is involved in a variety of physiological processes in higher plants. The novel gene product has a degree of similarity to mammalian β-11-hydroxysteroid dehydrogenase genes, known to control the conversion of steroids from active to inactive forms. In plants, the over expression of the HSD gene results in transgenic plants with significantly greater biomass and vigor, increased seed yield, increased tolerance to salt and a suppression of ABA mediated seed dormancy.
