# Seed dormancy is defined as a state in which seeds are prevented from germinating even under environmental conditions normally favorable for germination. These conditions are a complex combination of water, light, temperature, gasses, mechanical restrictions, seed coats, and hormone structures.
# Dormancy is a mechanism to prevent germination during unsuitable ecological conditions, when the probability of seedling survival is low. One important function of most seeds is delayed germination, which allows time for dispersal and prevents germination of all the seeds at the same time.
# Dormant seeds are unable to germinate even when the conditions for germination are favorable. There are ecological advantages for plants with seed dormancy. These include:
- 1. Delaying seed germination until the conditions for seedling survival are most favorable. For example, seeds may be shed from the plant in late summer or early fall. The germination conditions are favorable for germination, but because winter conditions will occur soon, it may not be the best conditions for seedling survival. By requiring seeds to receive several months of moist, chilling conditions to satisfy dormancy, these seeds will not be able to germinate until spring when conditions for seedling survival are higher.
- 2. To create a seed bank. A seed bank includes the seeds that are shed from the plant that do not germinate for years due to dormancy. A seed bank ensures that not all seeds of a species germinate in a single year. This is insurance against seedlings being exposed to catastrophic conditions (like drought or cold) that kill the entire next generation of a species. It also allows seedlings to grow during favorable years even if the mother plants failed to flower and make seeds.
# Many species of plants have seeds that delay germination for many months or years, and some seeds can remain in the soil seed bank for more than 50 years before germination. Some seeds have a very long viability period, and the oldest documented germinating seed was nearly 2000 years old based on radiocarbon dating.
# Seed dormancy is defined as a state in which seeds are prevented from germinating even under environmental conditions normally favorable for germination. These conditions are a complex combination of water, light, temperature, gasses, mechanical restrictions, seed coats, and hormone structures.
# Dormancy is a mechanism to prevent germination during unsuitable ecological conditions, when the probability of seedling survival is low. One important function of most seeds is delayed germination, which allows time for dispersal and prevents germination of all the seeds at the same time.
# Dormant seeds are unable to germinate even when the conditions for germination are favorable. There are ecological advantages for plants with seed dormancy. These include:
- 1. Delaying seed germination until the conditions for seedling survival are most favorable. For example, seeds may be shed from the plant in late summer or early fall. The germination conditions are favorable for germination, but because winter conditions will occur soon, it may not be the best conditions for seedling survival. By requiring seeds to receive several months of moist, chilling conditions to satisfy dormancy, these seeds will not be able to germinate until spring when conditions for seedling survival are higher.
- 2. To create a seed bank. A seed bank includes the seeds that are shed from the plant that do not germinate for years due to dormancy. A seed bank ensures that not all seeds of a species germinate in a single year. This is insurance against seedlings being exposed to catastrophic conditions (like drought or cold) that kill the entire next generation of a species. It also allows seedlings to grow during favorable years even if the mother plants failed to flower and make seeds.
# Many species of plants have seeds that delay germination for many months or years, and some seeds can remain in the soil seed bank for more than 50 years before germination. Some seeds have a very long viability period, and the oldest documented germinating seed was nearly 2000 years old based on radiocarbon dating.