Arisaema-offsets

[Jim McClements, Dover, DE z6]

In a message dated 1/25/00 11:50:08 AM, segawi at DDS.NL writes:

<<  I never use any force to detach offsets from the main tuber. You

sometimes see bulblets still (semi-)attached to the main tuber which should

be big enough to start a life of their own but you better leave them on. At

the end of next season they have increased in size even more and probably

have a better change of producing growth themselves. Offsets from section

Franchetiana (A. candidissimum, A. fargesii, A. franchetiana etc.) can often

be found well attached from the mother tuber and start to grow well next

season. The offsets from the stoloniferous species do the same as well as

those of A. thunbergii, A. nepenthoides and A. tortuosum. Most of the other

species I find more difficult. The offsets either die or stay dormant.

Rarely they "wake up" and then I think I have been rather lucky instead of

having the feeling I have done something right. It is all very well if you

get lots of bulblets but if they don't do thing, what's the purpose of

producing them? I have tried various methods of trying to awake them but

thus far in vain. Maybe they contain a growth inhibitor like those found in

seeds. Could there be a glibberilic acid-equivalent for bulblets? There must

be a controlled way of waking them up but what is it?


Pascal Bruggeman

Holland

>>

Pascal

I'm glad to hear someone else confirm this. I mentioned it in a posting last
year, but didn't get a rise out of anyone. It's frustrating to have a
well-intentioned friend send a few offsets and be unable to ever get them to
sprout, despite several cycles of alternating cold and warmth. I'm glad to
hear that some species aren't quite so stubborn.

The idea of a growth inhibitor has some appeal, but what would normally make
an inhibitor disappear when the tuberlet detaches from the mother? I would
almost think the opposite would be true, namely, that if there was some
inhibitor present while it was attached, it would be coming from the parent
and would no longer be present once detachment occurred. That's what's
thought to be the situation in trilliums, where "apical dominance" keeps
dormant buds from developing. Of course, removing  buds from trilliums
doesn't work either, unless they have matured to the point where roots are
present, often after the apical dominance is removed by decapitating the
parent. (This might work for Homo sapiens as well!) I would guess that there
is some maturity factor lacking in the arisaema tuberlets, but have no idea
what it might be. Has anyone tried GA3 or any of the other plant growth
hormones?

I hope we get some more input on this thread.

Jim McClements