How Seeds Grow: Germination

Germination is the process by which an organism grows from a seed or spore. It involves the reactivation of metabolic processes, enabling the embryo to emerge from the seed coat.

The process relies on internal and external stimuli. Water uptake (imbibition) activates hydrolytic enzymes that convert stored starch, proteins, or oils into energy. Aerobic respiration provides the necessary ATP until the seedling develops photosynthetic capabilities.

Germination is the most vulnerable stage in a plant's life cycle. Successful establishment is essential for population survival, and understanding the germination index helps in assessing soil health and potential phytotoxicity.

Research into seed physiology has revealed that dormancy is regulated by hormones like abscisic acid (inhibitor) and gibberellin (promoter). Scientists have also discovered that seeds possess DNA repair mechanisms to fix genome damage accumulated during aging.

In industrial applications, such as brewing, barley seeds are treated with gibberellin to ensure uniform germination. Additionally, ecological studies show that some species require 'scarification'-mimicking natural events like forest fires-to break physical dormancy.