In order for a seed to germinate, many conditions must be met. Firstly a seed must be viable. If a

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In order for a seed to germinate, many conditions must be met. Firstly a seed must be viable. If a seed is viable it require a suitable environment with proper levels of moisture, suitable temperatures, oxygen, fertile soil, and proper pH levels to name a few. However, as many of us have experienced, some viable (living) seeds will NOT germinate, even when given the perfect conditions. In the field of botany, this phenomenon is known as “physiological seed dormancy” (will be referred to as PSD from here on out). In plain language, PSD is like a “hibernation” stage that occurs after seed maturation but before germination. After the seeds of a mother plant mature, they respond to environmental cues that signal the end of the growing season…show more content…
The answer is ABA) In contrast to mature plant, in seeds ABA is mainly produced in the cotyledons (1st set of “immature leaves”) of an embryo and is secreted inside the seed at a very slow and constant rate. This will inhibit germination. A sharp decrease in ABA levels disrupts PSD, triggers embryo growth, and thus allows germination. There are many ways by which ABA levels can be decreased. The most understood methods include: Chilling, Phytochrome stimulation, and After-ripening. Chilling is another way to decreases levels of ABA. Chilling disrupting the enzymes that catalyze the reaction that make ABA. This occurs in nature during the cold temperatures of winter. seeds that have fallen to the ground are covered by snow or cold soil for 2-4 months and disrupt the production of ABA. This can simulated through a process in botany known as “stratification”. seeds are placed in MOISTENED medium or paper towel and kept in a REFRIGERATOR to simulate winter and disrupts the production of ABA. (Do not use the freezer, your run the risk of tissue damage once temperatures fall below 32F. Temperatures between 34F-40F work best. 3-14 days usually works for cannabis, but some seeds may require longer. The longer they are in cold, the more likely levels of ABA will
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