1. Greenhouse Management
Seed Dormancies
Greenhouse Management

2. Seed Terminology
Viable: the seed has a “living” embryo and is capable of germinating.
Germination test: The percentage of seed, in any given sample size, that actually germinate.
For example if you sowed 100 seeds and 86 out of the 100 germinated, what would the percent germination be?

3. Definition of Dormancy
The failure of a seed to germinate even though the requirements for successful seed germination are all present.
Moisture
Temperature
Oxygen
Sometimes light

4. Types of Seed Dormancies
Physical
Physiological
Photodormancy
Double Dormancy

5. Physical Dormancy Cause Treatments
Seed has a hard seed coat is impermeable to water.
*Scarification
A – Acid
B – Mechanical
C – Hot Water

6. Physiological Dormancy
Cause
Treatments
Seed has a dormant embryo.
*Cold stratification
A – moist
B – aerated
C – proper temperature
D – proper time

7. Photodormancy Cause Treatments
Seeds will not germinate until they are exposed to a certain amount of red light.
*Expose seeds to red light. Seeds must first be in an imbibed state.

8. Double Dormancy Cause Treatments
Combination of several different kinds of dormancies present in a seed at the same time.
*Sequential treatments to handle each type of dormancy.

9. The End