Re: HYB: removing germ. inhibs. part 3

Now that I've made a big deal of distinguishing between seed coat and
embryo dormancy, I have to add that Vallette doesn't distinguish between
the two, & it isn't always clear from her writing whether or not seeds
were chilled after various soakings.  Reading between the lines, most if
not all the methods I'm including in this post improve germination rate
(i.e., percent of seeds that germinate the first year) but don't
eliminate the need for chilling.

Sulfuric acid (Vallette, page 154):
"....soaking seeds one hour in concentrated sulfuric acid, rinsing well,
then storing in the deep freeze for two weeks.  Of 12 treated seed [no
information given on cultivars involved], 11 came up, but soaking for
1.5 hrs resulted in only three, and for 30 minutes, nine.  Great care
must be used..".. etc

Chloride of lime (same page)
"...soaking ..overnight in a solution of 1 tb.[?I assume that's 1
Tablespoon?] chloride of lime of 2 qts. water, then using the dull [bold
letters] edge of a knife the next morning to lift off the hypocotyl,
where the sprout emerges from the seed, and planting....gave almost
perfect germination.... Just soaking in the solution for 24
hrs...[resulted in] over 95% first-year germination ... with no further
treatment"  [It isn't clear to me if 'no further treatment' means they
germinated immediately.]

removing the seed coat (pate155)
"Germination is said to often be improved by completely removing the
seed-coat, or by soaking a short time in boiling water or lye-water -
not too long, or seed may be killed [unfortunately, she doesn't say how
long is too long ;-(].  Soaking, then removing the seed-coat (testa) at
the growing point is said to more than double the number of seed that
come up, and decapping seems to be almost as good. [again, it's not
clear whether seeds still must be chilled in order to germinate.]

Clorox, p156
"...soaking Lilliput seed in a 50-50 chlorox [sic] solution ...They were
forgotten and soaked for three hours, and though all white and
blistered, they came up much sooner and better than similar seed that
had not been soaked....[75% vs10%]...."
[or] "...freezing seed for a day or so, then soaking them 24 to 48 hours
in a 25% chlorox [sic] solution, and getting 100% germination within 2
weeks."

==That last one is worth a try!==

Enough for now.
--
Linda Mann east Tennessee USA zone 7/8
East Tennessee Iris Society <http://www.korrnet.org/etis>
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