Germination
Erica's Original Notes: Germination starts when colloidal inhibition is overtaken by osmotic forces and water is taken in to the seed; that is, in plain English, when the seed coat has broken down and water enters the seed to stimulate growth.
Desert annual seeds (desert ephemerals) only respond to a downpour of rain which is sufficient to complete their life cycle. Winter annual seeds respond to water and lower temperatures. Summer annual seeds respond to water and heat. Other influences on germination of seeds are daylight sensitivity, when light is needed (birch and foxglove), and darkness (lily family amongst others).
Winter cold is needed by some seeds to trigger the cycle; spruce seed has a hibernation spell to prevent germination and winter kill.
A seed is a safe deposit for the plant's future; a 1000-year-old lotus seed, found in a bog germinated! (See Note 1 below.)
See also Erica's notes on Seeds.
NOTES Updated 2013 (RP):
1. SHEN-MILLER, J., M. B. MUDGETT, J. W. SCHOPF, S. CLARKE, AND R. BERGER. 1995. Exceptional seed longevity and robust growth: ancient Sacred Lotus from China. American Journal of Botany 82: 1367–1380.
Shen-Miller obtained seven lotus seeds from the Chinese village of Pulantien in 1982 from the Beijing Institute of Botany. She determined the dates of six of them and germinated four of them. The oldest was calculated to be 1,288 years old, give or take 271 years. The youngest was 95 years old. She planted the 332-year-old seed in a tub in the courtyard of her home, where it sprouted many leaves, grew faster than modern lotus plants and lived for nine months.
Desert annual seeds (desert ephemerals) only respond to a downpour of rain which is sufficient to complete their life cycle. Winter annual seeds respond to water and lower temperatures. Summer annual seeds respond to water and heat. Other influences on germination of seeds are daylight sensitivity, when light is needed (birch and foxglove), and darkness (lily family amongst others).
Winter cold is needed by some seeds to trigger the cycle; spruce seed has a hibernation spell to prevent germination and winter kill.
A seed is a safe deposit for the plant's future; a 1000-year-old lotus seed, found in a bog germinated! (See Note 1 below.)
See also Erica's notes on Seeds.
NOTES Updated 2013 (RP):
1. SHEN-MILLER, J., M. B. MUDGETT, J. W. SCHOPF, S. CLARKE, AND R. BERGER. 1995. Exceptional seed longevity and robust growth: ancient Sacred Lotus from China. American Journal of Botany 82: 1367–1380.
Shen-Miller obtained seven lotus seeds from the Chinese village of Pulantien in 1982 from the Beijing Institute of Botany. She determined the dates of six of them and germinated four of them. The oldest was calculated to be 1,288 years old, give or take 271 years. The youngest was 95 years old. She planted the 332-year-old seed in a tub in the courtyard of her home, where it sprouted many leaves, grew faster than modern lotus plants and lived for nine months.