RickCorey said:
MAYBE it also deactivates SOME kinds of germination inhibitors (helps break dormancy).
By some mechanism hydrogen peroxide breaks seed dormancy in daylily seeds. I did an experiment comparing daylily seeds I knew had a high percentage of seed dormancy. I had some soaking in hydrogen peroxide at various dilutions, some soaking in plain water, and some planted in vermiculite as a control. Those in hydrogen peroxide germinated well, better than the control, while those soaking in plain water had worse germination than the vermiculite control. None of the seeds had been stratified beforehand.
Quoting one scientific research article for zinnia seeds, it is not believed to be due to the extra oxygen released but instead their findings indicated that "oxidation of the germination inhibitor(s) present in the pericarp by H2O2 promotes seed germination. Antioxidants which are derivatives of well-known germination inhibitors suppressed seed germination in a dose-dependent manner, suggesting that, to initiate seed germination, a germination inhibitor(s) should be decomposed by an oxidant such as H2O2." The full Plant and Cell Physiology journal article is here:
http://pcp.oxfordjournals.org/...
I don't have time right now to read it right through again, but daylily seeds aren't supposed to have germination inhibitors according to some old research. They certainly don't have a seed dormancy that is broken by soaking in water, a method which actually inhibited germination in my experiments. H2O2 doesn't work for all daylily seeds, according to what some people have told me who found a limited number of seeds did not respond. Those same seeds did germinate when stratified after the H2O2 failed, so I'm told.
