Graduation date: 2007Seed germination sensu stricto is defined as the physiological events before the radicle tip ruptures the covering tissues. The ability of the radicle to elongate (or germination potential) is observed in developing embryos prior to completion of seed maturation. When embryos at early developmental stages, such as globular, heart, torpedo or walking-stick are excised and grown in media, germination potential is not observed. Following these stages, embryos start to acquire germination potential. This thesis research focused on the mechanisms of the induction of germinability in Arabidopsis thaliana (Arabidopsis) developing seeds. A mutant with embryo defects was also analyzed in this research to gain insights into embryogenesis and germination. The mutant named embryo ball (eb) arrests after the globular-like stage yet continued cell growth to some extent. While desiccated mature eb seeds were unable to germinate, if developing embryos were excised and placed on media, the main root elongated. eb also exhibited abnormal root hair growth from the apical portion of the embryo. The hypocotyl and cotyledons were missing in eb embryos in mature seeds. When eb embryos were grown on media, vegetative leaf-like structures with trichomes were formed and the main and subsequent lateral roots developed normally. Some eb embryos exhibited desiccation tolerance which is characteristic of wild-type (WT) mature embryos. Thus, while morphological maturation does not seem essential for the induction of germination potential, physiological maturation of the embryonic cells plays an important role in determining germination potential.