The Effect of External Conditions upon the After-Ripening of the Seeds of Crataegus mollis

  title={The Effect of External Conditions upon the After-Ripening of the Seeds of Crataegus mollis},
  author={Wilmer E. Davis and R. Catlin Rose},
  journal={Botanical Gazette},
  pages={49 - 62}
It is well known that the seeds of many plants do not germinate immediately after ripening, but only after a period of rest which in some cases no doubt extends into years. NOBBE and HANLEIN (i6), for example, kept certain weed seeds under germinating conditions for a period of II73 days without germination. While various workers have done much in the way of adding to the list of seeds that require a rest period before germination, little has been done to determine the real cause of this delay… 
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Results from seeds planted in soil in greenhouse flats and stratified outdoors during the winter for various periods indicated that 1 or 2 months of stratification sufficed for the breaking of dormancy, and after-ripening occurred only at low temperatures and when the seeds were moist.
A Physiological and Chemical Study of After-Ripening
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In nature growth of the delayed seeds comes about through the disintegration of the seed coat structures by a longer or shorter exposure to germinative conditions, and the length of the delay depends upon the persistence of the structure securing it.
Longevity of Seeds
EWART finds the resistance in Adansonia digitata to be due to the impermeable nature of all layers of the integument, and I find the same to be true of the hard seed of Axyris amaranthoides.
Pfeffer's Physiology of Plants
Physiology of plants.
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S Physiology of plants
    Viability of weed seeds under different conditions of treatment and study of their dormant periods
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