Contractile roots

From: Mike Bordelon <BORDELON.MIKE at NMNH.SI.EDU> on 1997.09.03 at 23:28:58(1155) Hello everybody, A recent discussion on AEG about contractile roots on Arisaemas prompted this question. I dug Amorphophallus muelleri from a bed yesterday and they appeared to be at the same depth of planting. I know they have roots that emerge from the top to stabilize the plant, but do Amorphophallus also have contractile roots to pull them further into the soil ? Mike Bordelon

From: "Don Bittel" <dbittel at treco.net> on 1997.09.08 at 13:13:01(1182) Mike, My theory is that Amorphophallus do not have contractile roots. Instead, the rotting away of the old tuber allows the new tuber to 'fall' into the hole that is left, thus lowering the tuber deeper each time. This allows it to stabilize itself better as it grows larger and larger. I have noticed this on all of my species when I used to dig them up every winter. They got so deep that now I just leave them in the ground. In this part of Florida we rarely get a hard freeze anyway. There must be some stopping point to this, however, or it could eventually sink down to the water table and rot away! I would be happy to hear from Wilbert or anyone else on this subject also. +More ---------- > From: Mike Bordelon > To: dbittel@treco.net > Subject: Contractile roots > Date: Wednesday, September 03, 1997 7:30 PM > > Hello everybody, > A recent discussion on AEG about contractile roots on > Arisaemas prompted this question. I dug Amorphophallus > muelleri from a bed yesterday and they appeared to be at the > same depth of planting. I know they have roots that emerge > from the top to stabilize the plant, but do Amorphophallus > also have contractile roots to pull them further into the soil ? > > Mike Bordelon >

From: Wilbert Hetterscheid <hetter at vkc.nl> on 1997.09.08 at 16:03:22(1187) Don Bittel's answer to Mike Bordelon's question has one flaw. Amorphophallus DO have contractile roots. Just have a look at older roots at the top of the tuber when you take one out. It is especially noticeable on larger plants. The "drop in the hole" idea will certainly be true but without the contractile roots, the whole structure would tumble to its side for lack of anchorage. Wilbert +More > ---------- > From: Don Bittel[SMTP:dbittel@treco.net] > Reply To: aroid-l@mobot.org > Sent: maandag 8 september 1997 15:11 > To: hetter@vkc.nl > Subject: Re: Contractile roots > > Mike, > My theory is that Amorphophallus do not have contractile roots. > Instead, > the rotting away of the old tuber allows the new tuber to 'fall' into > the > hole that is left, thus lowering the tuber deeper each time. This > allows it > to stabilize itself better as it grows larger and larger. I have > noticed > this on all of my species when I used to dig them up every winter. > They got > so deep that now I just leave them in the ground. In this part of > Florida > we rarely get a hard freeze anyway. There must be some stopping point > to > this, however, or it could eventually sink down to the water table and > rot > away! I would be happy to hear from Wilbert or anyone else on this > subject > also. > > ---------- > > From: Mike Bordelon > > To: dbittel@treco.net > > Subject: Contractile roots > > Date: Wednesday, September 03, 1997 7:30 PM > > > > Hello everybody, > > A recent discussion on AEG about contractile roots on > > Arisaemas prompted this question. I dug Amorphophallus > > muelleri from a bed yesterday and they appeared to be at the > > same depth of planting. I know they have roots that emerge > > from the top to stabilize the plant, but do Amorphophallus > > also have contractile roots to pull them further into the soil ? > > > > Mike Bordelon > > >

From: Rand Nicholson <writserv at nbnet.nb.ca> on 1997.09.08 at 19:37:10(1189) >Don Bittel's answer to Mike Bordelon's question has one flaw. >Amorphophallus DO have contractile roots. Just have a look at older >roots at the top of the tuber when you take one out. It is especially >noticeable on larger plants. The "drop in the hole" idea will certainly >be true but without the contractile roots, the whole structure would >tumble to its side for lack of anchorage. > >Wilbert +More Would the new tuber not also grow into the old cavity as the old tuber collapses? Rand

From: MJ Hatfield <oneota at ames.net> on 1997.09.09 at 12:57:08(1191) Wilbert said "contractile roots. Just have a look at older roots at the top of the tuber when you take one out." Please enlighten me. I don't know what a contractile root looks like. Thanks. MJ Hatfield

From: Wilbert Hetterscheid <hetter at vkc.nl> on 1997.09.09 at 13:10:13(1193) Rand, Yes, it would indeed grow in the old cavity which is in line with what Don Bittel said. But there is always that moment when there is less tuber than cavity at which time the plant needs to be anchored or it would become unstable. I have seen this in my own collection and it is known from plants in the wild: if you dig them out when the leaf has just emerged, you may not find a shred of tuber and the petiole is kept in place by the horizontal contractile roots and the soil surrounding the base of it. Cheers, Wilbert +More > ---------- > From: Rand Nicholson[SMTP:writserv@nbnet.nb.ca] > Reply To: aroid-l@mobot.org > Sent: maandag 8 september 1997 21:36 > To: hetter@VKC.NL > Subject: RE: Contractile roots > > >Don Bittel's answer to Mike Bordelon's question has one flaw. > >Amorphophallus DO have contractile roots. Just have a look at older > >roots at the top of the tuber when you take one out. It is especially > >noticeable on larger plants. The "drop in the hole" idea will > certainly > >be true but without the contractile roots, the whole structure would > >tumble to its side for lack of anchorage. > > > >Wilbert > > Would the new tuber not also grow into the old cavity as the old tuber > collapses? > > Rand > > >

From: Krzysztof Kozminski <kk at netgate.net> on 1997.09.09 at 21:01:23(1201) On Tue, 9 Sep 1997, MJ Hatfield wrote: > Wilbert said "contractile roots. Just have a look at older > roots at the top of the tuber when you take one out." > Please enlighten me. I don't know what a contractile root looks like. > Thanks. See +More http://ng.netgate.net/~kk/Araceae/Amorphophallus/bulbifer.HAM_136.html#bulbifer.HAM_136.3 for a photo of emerging roots in a non-contracted state. Basically, they are somewhat elastic and their tension holds th tuber in place. On the older tubers, just after they go dormant, the same roots have a pleated appearance, somewhat reminding of accordion bellows. You can stretch them (a little only, as they are dead and not functional any more) and they shrink back. ==================== Krzysztof Kozminski kk@netgate.net http://www.netgate.net/~kk/

From: Roger Sieloff ISDH <sieloff at doe.state.in.us> on 1997.09.10 at 04:03:45(1210) On Tue, 9 Sep 1997, MJ Hatfield wrote: > Wilbert said "contractile roots. Just have a look at older > roots at the top of the tuber when you take one out." > Please enlighten me. I don't know what a contractile root looks like. > Thanks. > MJ Hatfield +More Here's my two scents: Last spring I harvested quite a few Arisaema seedlings that were generously donated to me as seeds by the A. study group. While wrenching the tender little things from their styrofoam nurseries, I noticed the roots were unusually wrinkled in appearance and as I tugged at them unmercifully a wierd phenomenon occured - the "skin" revealed itself to be as loosely bound to the underlying root as human arms are inside shirtsleeves, i.e., the sheath slid very easily along the entire length of the root, indicating a theoretical facility of drawing the developing tubers (corms?) deeper into the soil as they matured. Amorphophallus roots don't seem to be anything like this. I don't believe Arisaema tubers consume themselves after the leaf matures like Amorphophallus tubers seem to do. Therefore it seems plausable the Arisaemas might be pulling themselves down into the substrate as they mature while Amorphophallus appear to be simply bulldozing deeper and deeper cavities as each spring's tuber is consumed and the hollow space is refilled with a larger tuber. Maybe ... Theoretically yours, Roger L. Sieloff

From: Wilbert Hetterscheid <hetter at vkc.nl> on 1997.09.10 at 16:14:49(1211) Mary Jane, A contractile root looks like an ordinary root but the "skin" is heavily wrinkled as if pushed up from one side over the inner tissues. Does that make sense? +More Cheers, Wilbert > ---------- > From: MJ Hatfield[SMTP:oneota@ames.net] > Reply To: aroid-l@mobot.org > Sent: dinsdag 9 september 1997 14:54 > To: hetter@vkc.nl > Subject: Re: Contractile roots > > Wilbert said "contractile roots. Just have a look at older > roots at the top of the tuber when you take one out." > Please enlighten me. I don't know what a contractile root looks like. > Thanks. > MJ Hatfield > > >

From: MJ Hatfield <oneota at ames.net> on 1997.09.11 at 14:08:32(1222) Yes, I now understand contractile roots. Yesterday I dug up both an Amorphophallus and an Arisaema to look at the roots (they were ready to be dug anyway, I think). Do Arisaema have contractile roots too? Both species seemed to have them. Another surprise. I was crawling around looking at the plants in my aroid bed and there, next to the ground, was a Sauromatum seed head with what look like immature but fertile seeds. I know they bloomed after being planted outside but I didn't know I had the proper pollinators. I guess so. (Not quite as striking as the seed head of my A.konjac last year.) +More MJ hatfield

From: hallsa at sirius.com (Steve Hall) on 1997.09.11 at 16:44:36(1226) >Another surprise. I was crawling around looking at the plants in my >aroid bed and there, next to the ground, was a Sauromatum seed head with >what look like immature but fertile seeds. Much to my surprise, two of my Sauromatum produced seed heads this year. Can any one give me some advice on how to harvest these seeds? Steve Hall

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