Skip to Content.
Sympa Menu

nafex - Re: [NAFEX] Hardening-off Question

nafex@lists.ibiblio.org

Subject: North American Fruit Explorers mailing list at ibiblio

List archive

Chronological Thread  
  • From: Ginda Fisher <list@ginda.us>
  • To: North American Fruit Explorers <nafex@lists.ibiblio.org>
  • Subject: Re: [NAFEX] Hardening-off Question
  • Date: Wed, 10 Aug 2005 17:29:01 -0400


On Aug 10, 2005, at 9:46 AM, Lucky Pittman wrote:

At 07:18 AM 8/10/2005, J.Fruth wrote:

   Here's a question a lot of us wold like to know the answer to:  Does
anyone have an answer?  "Physiologically speaking, what happens inside the
branches, twigs, trunk, etc. of fruit trees as the harden off for the
winter?"


Jim,
I'm not a plant physiologist/pathologist, but I suspect the answer lies in 
the degree of lignification - development of increasing amounts of lignins 
- the compounds which give woody plants(as well as grasses) much of their 
structural integrity.

Lucky

I am also no specialist, but I would guess that another part of the answer is the amount of water in the tissue.  I bet the tree dries itself out, increasing the concentration of other "stuff" dissolved in the sap to increase the freezing point of the remaining liquids and to decrease the damage that swelling of freezing liquids would otherwise cause.

This is purely a guess, but I know that in animal cells a lot of the damage from freezing is actually mechanical damage to the cell membranes caused by swelling water and ice crystals.

Ginda



Archive powered by MHonArc 2.6.24.

Top of Page