**Seed Dormancy: The Complex Process Regulated by Abscisic Acid, Gibberellins, and Other Phytohormones that Makes Seed Germination Work**

Anna Skubacz and Agata Daszkowska‐Golec

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.68735

#### **Abstract**

Seed dormancy is one of the most important adaptive mechanisms in plants, which pro‐ tects seeds from precocious germination in the presence of the inappropriate conditions for growth continuation. Numerous environmental and molecular signals regulate seed dormancy. Maintenance or release of seed dormancy is dependent on light, temperature, and water availability. Precise response of seeds to environmental factors is mediated by different phytohormonal pathways. ABA is considered as a main phytohormone regulat‐ ing seed dormancy induction and maintenance. ABA‐ and GA‐responsive components, ensure crosstalk between the GA and ABA pathways and enable seed response adequate to the environment. Phytohormonal regulation mechanism of seed dormancy is similar in dicot and monocot plants. Recently, it is suggested that other phytohormones, such as auxin, jasmonates, brassinosteroids, and ethylene, also take part in seed dormancy regu‐ lation. Auxin regulators, enhance ABA action and positively influence seed dormancy. However, jasmonates, brassinosteroids, and ethylene reduce seed dormancy level. Here, we describe recent advances in understanding the complex process of seed dormancy regulated by many phytohormonal pathways and their components. Seed dormancy studies can help obtain crop varieties producing seeds with the most desirable timing of germination.

**Keywords:** seed dormancy, germination, abscisic acid, gibberellic acid, phytohormone crosstalk

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