Well, our esteemed Japanese colleague Isao Takai recently sent to me
a message in which he described a method he used to successfully induce
germination from six batches of seed (he noted this technique did not work
for other packets). Furthermore, he didn't use a control group from each
sample so it is possible they may have germinated anyway. In any event,
here is the technique he used.
He filled a 35mm film case with water, dropped in the seed, and used a
top layer of gauze (I'm not sure why). By successive periods of short-term
freezings (yes, I said FREEZING), he waited until the seeds sank instead
of floated. Then he judged the seeds ready for planting.
This is extremely interesting to me. I have successfully induced germination
in the boreal species _D.linearis_ by freezing the seeds (sown in a small pot)
for several weeks, but had never considered using the method on _Sarracenia_.
Can anyone tell me why ``sinking seeds'' is considered an indication for
germination readiness? Does it indicate a water-repellent seedcoat has
hydrated?
____________________
Isao's excellent email graphics and edited description follow:
------------
|| ||
|ssssssssss| s:seeds
|----------| <- water level
| |
| |
| |
| |
------------
------------ ------------
|| || || ||
|GGGGGGGGGG| G:gauze |GGGGGGGGGG|
|----------| |----------|
|ssssssssss| | |
| | freeze it 3 or 5 times -> | |
| | | |
| | | |
| | |ssssssssss|
------------ ------------
I put the film case into a freezer in the evening. Next morning I take it out
and let it thaw at room temperature. And in the evening I put it into freezer
again, repeating the process over and over again until the seeds sink to the
bottom of the film case.