Abstract Introduction Among the most important functions of plant hormones is controlling and coordinating cell division, growth and differentiation. Plant hormones can affect different plant activities including seed dormancy and germination. Plant hormones including abscisic acid (ABA), ethylene, gibberellins, auxin (IAA), cytokinins, and brassinosteroids are biochemical substances controlling many physiological and bio-chemical processes in the plant. These interesting products are produced by plants and also by soil microbes. Auxin is a plant hormone, which plays a key role in regulating the following functions: cell cycling, growth and development, formation of vascular tissues and pollen and development of other plant parts. Cytokinins are plant hormones, regulating a range of plant activities including seed germination. They are active in all stages of germination.