Re: HYB: REB: ? hormones & rebloom?

This may have nothing to do with abscisic acid in seeds with delayed germination, but it made me wonder. Betty, this sounds as though seeds produced in our climate might have delayed germination, but seeds produced from the same cross in a more hospitable climate might not. Or less so. depending... maybe...
One role of ABA that is well documented is as a stress hormone. When a plant is subjected to difficult environmental conditions, such as very
high temperatures, or very reduced water supplies, then it responds by secreting ABA. In a plant under drought conditions, the concentration of ABA in the leaves can rise to forty times that which would normally be present. This high concentration of ABA causes the stomata to close, which reduces loss of water vapour from the leaf. 

Functions of Abscisic Acid
The following are some of the physiological responses known to be associated with abscisic acid (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).

    * Stimulates the closure of stomata (water stress brings about an increase in ABA synthesis).
    * Inhibits shoot growth but will not have as much affect on roots or may even promote growth of roots.
    * Induces seeds to synthesize storage proteins.
    * Inhibits the affect of gibberellins on stimulating de novo synthesis of a-amylase.
    * Has some effect on induction and maintanance of dormancy.
* Induces gene transcription especially for proteinase inhibitors in response to wounding which may explain an apparent role in pathogen defense. 


--
Linda Mann east Tennessee USA zone 7/8
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