Seed germination is controlled by a number of mechanisms and is necessary for the growth and development
of the embryo, resulting in the eventual production of a new plant. Under unfavorable conditions
seeds may become dormant (secondary dormancy) to maintain their germination ability. However, when
the conditions are favorable seeds can germinate. There are a number of factors controlling seed germination
and dormancy, including plant hormones, which are produced by both plant and soil bacteria.
Interactions between plant hormones and plant genes affect seed germination. While the activity of
plant hormones is controlled by the expression of genes at different levels, there are plant genes that are
activated in the presence of specific plant hormones. Hence, adjusting gene expression may be an effective
way to enhance seed germination. The hormonal signaling of IAA and gibberellins has been presented
as examples during plant growth and development including seed germination. Some interesting results
related to the effects of seed gene distribution on regulating seed activities have also been presented. The
role of soil bacteria is also of significance in the production of plant hormones during seed germination, as
well as during the establishment of the seedling, by affecting the plant rhizosphere. Most recent findings
regarding seed germination and dormancy are reviewed. The significance of plant hormones including
abscisic acid, ethylene, gibberellins, auxin, cytokinins and brassinosteroids, with reference to proteomic
and molecular biology studies on germination, is also discussed. This review article contains almost a
complete set of details, which may affect seed biology during dormancy and growth