seeds dormancy & germination

[Ian Staples]

waverheu at vub.ac.be (Willy A Verheulpen) writes:

>Hello everyone,
>Does anyone have any info on enhancing seeds germination.
>This interests me very much. The striation/scratching &
>sulphuric acid treatments are known in the raising
>of many plant species.(I am mainly interested in cacti)
>I am more interested in experiments that show a chemical/
>biochemical or other influence that breaks seeds dormancy
>and that is able to amplify the seeds germination rate.

Potassium nitrate is *very* commonly used in standard germination
tests (e.g. "International Rules for Seed Testing 1985"), especially
to break dormancy in *fresh* grass seed (i.e. cereals and pasture
grasses).  It is used as a 0.2% aqueous solution for the *initial*
wetting of the test only - use pure water for subsequent "top-ups"
if required.

Giberellic acid is also specified for some species in the "Rules",
but I don't have the full details available: you need to see
"Annexe 5.6.4.A" for these.  You should be able to find the full
1985 Rules and Annexes in _Seed Science and Technology_ Vol.13 No.2
(1985).  I don't know if there has been an update since then.

KNO3 is often used after preliminary sulphuric acid scarification
or "Prechill" (I may be confused here - it may be an alternative
to these treatments, my extract is not clear on this point 8-)
Similarly, GA3 is commonly associated with "Preheat" &/or "Prechill"
(but not with H2SO4 that I noticed in a quick scan).

Cheers,  Ian S.

-- 
Ian Staples                        E-mail : ianst at qdpii.ind.dpi.qld.gov.au
c/- P.O. Box 1054 MAREEBA          Phone  : +61 (0)70 921 555 Home 924 847
Queensland Australia 4880            Fax  : +61 (0)70 923 593   "   "   "