Date: 30 Jul 1997 12:46:12 +0100 From: Loyd Wix <Loyd.Wix@unilever.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg2865$foo@default> Subject: Ping seed germination and germination inhibitors
Dear all,
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following on from Marcels request recently I though I would =
share some experience I have had this year on germinating =
European Pinguicula seed without a stratification period.
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Conventional Adrian Slack wisdom instructs you sow your =
seeds then expose them to frost durring the winter to =
stratify the seeds. Great! But what happens if you receive =
seeds in the spring or summer with no frosty nights? Hold =
onto the seed until Winter and perhaps loose viability - or =
you could place the pots/trays into the deep freeze though I =
have not found this to be successful. Well here follows a =
tale of germinating Euro Pinguicula without Stratification : =
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I have recently made a break through in the germination of =
P.alpina seed. I have been trying to germinate this species =
since 1990 with no success. I have tried seeds from many =
sources and localities including seeds freshly harvested by =
friends. This had been most frustrating as I have germinated =
many Euro - Pinguicula from seed and could not understand =
why P.alpina should be so difficult.
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This year I tried a different approach for a variety of =
reasons. I was sent some seed by a pal in central Europe =
which included 3 different locations/forms of P.alpina and =
some P.vulgaris. It was too late in the year for any frost =
to stratify the seed and I didn't want to put the seed into =
my deep freezer. I remember reading an article by Miloslav =
Studnicka on a method he uses to store Euro - Pinguicula =
seed for prolonged periods of time. His method involves =
soaking the seed in water to remove the abscisic acid (ABA) =
and in the dark to avoid germination - such treated seed =
would maintain good viability for several years. I decided =
to use this method to remove the ABA so the seed would not =
need to be stratified, and placed the seed in plastic =
containers with approx 200ml of cooled boiled water. I =
exposed the containers to light to deliberately promote =
germination. After 5 to 6 weeks germination had occurred =
with all seeds, with some germination occurring with the =
P.alpina seed collected in 1995 thus the seed would appear =
to maintain viability for longer periods than we have been =
lead to believe. Once germination had occured it was simply =
a matter of transfering the small seedlings onto compost =
using a small pipette. I am sure this method could be used =
for other species of European Pinguicula other than P.alpina =
and P.vulgaris.
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This method may be of use to germinate other difficult to =
germinate seed or seed requiring stratification. Earlier =
this year Eric Green mentioned Allen Lowries method he uses =
to germinate difficult Northern Australian Utrics and South =
American Genlisea. He has written to me on the same subject =
and think he wrote an article in the Aussie CP journal. =
Basically he maintains high temperatures (25=B0C plus) and =
water the pots from above 3 times a day. I suspect this =
overhead watering may disperse germination inhibiting =
chemicals such as ABA from the seeds. When pots are treated =
normally i.e. watered from beneath using the tray system, I =
suspect that the surface film of water on the compost =
contains many dissolved organic chemicals from the peat and =
also inorganic salts. This solution is probably not very =
effective in dispersing germination inhibiting substances. =
Thus to get some species of CPs which have constant water =
movement in their natural environments germination maybe =
enhanced by suspension in water or through frequent over =
head watering.
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This brings me back to Adrian Arnolds recent posting on =
avoiding green slime, and whether the germination he has =
achieved is through avoiding the slime or whether the =
overhead watering has dispersed inhibiting substances. =
Certainly Adrians technique to avoid slime is similar to =
Lowries germination method.
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Looking forward to comments.
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Regards
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Loyd
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