Experiment follow-up

[McClements, Jim]

AEGrs

As some of you may remember, about a year ago I started an experiment trying
to determine the best way to store arisaema seeds. I introduced two
variables:

1. refrigeration vs. room temperature
2. storage in berry vs. removed from berry

Four groups of 20 seeds from the same plant of Arisaema sikokianum, a species
which germinates readily when fresh, without any need for a cold period, were
subjected for 6 months to the following storage methods:

a. refrigerated in berry, in glassine envelope
b. refrigerated removed from berry, in glassine envelope
c. room temp in berry, in paper envelope
d. room temp removed from berry, in paper envelope

After (a) and (c) were removed from the berry, all seeds were  soaked in a
detergent solution for 30 minutes, and then placed in damp towels on June 12,
1997. Radicles were developing by June 25 in all groups, and on June 29 all
seeds were planted in wet turface and placed under lights. At that point it
appeared that approximately 50% of each group had germinated.

However, the final results are quite different from the preliminary
impression.

a. germ 19 of 20
b.   "      17 of 20
c.   "      12 of 20
d.   "      10 of 20

While I'm no statistician and have forgotten all I ever learned about Chi
square, etc., I think it's clear that groups (a) and (b) ,the seeds
refrigerated in glassine envelopes, fared much better than (c) and (d), kept
at room temp. in paper envelopes, It made no significant difference if the
seeds were left in the berry or stored "bare".

The questions are, "Did the cold have a beneficial effect itself, or did it
merely retard the drying-out process?  Did the glassine vs paper make any
difference?" (Now I wish that I had used the same envelope for all four
groups. I introduced another variable without meaning to do so.)

Since Arisaema sikokianum germination doesn't normally seem to be influenced
by a cold period if planted fresh, I'm inclined to think that prevention of
drying may be more important than the temperature itself, but, whatever the
reason, I think I will continue to store Arisaema seed in the refrigerator,
in glassine, whenever possible.

And, on another subject, I sent some seed to quite a few AEGrs last year from
an unidentified arisaema from Carol Fyler's garden. Mine have finally
germinated copiously, but only after TWO periods in the refrigerator. So
don't give up. (Still unidentified).

Jim McClements