Re: [Aroid-l] Thorns on Aroids

From: <ju-bo at msn.com> on 2009.02.27 at 10:22:40(19143) Dear Beth and All Great idea Beth! Lots more research is needed by folks in the field like you Miss Beth to observe exactly WHY for example climbing Aro ids don`t manage to ''stick'' themselves to the spiny trunk of a Ceiba tree . Could it be additional factors beside just the spines like rapidly pe eling bark as the trunk of the tree expands which may discourage root attac hment? By the way thanks to Marek for reminding us of the sppines on Anchomanes (and this brings to mind Pseudohydrosme a close (?) relative). We must also keep in mind the not-so-old but now extinct Magafauna (thro ugh man`s hunting?) and maybe other medium-to-small sized animals which until fairly recently existed through the Neotropics (and further North int o N. America). These animals evolved together with the plants (which stil l exist) so we really need to try to learn and understand what roles the se now-extinct animals played in the evoloution of the defense mech. AND th e distribution of fruit and seeds of these still existing plants. Just yesterday I was reading about certain trees and plants on New Zealand which are today rare and growing rarer the thoughts are that the now-ext inct giant Ostrich-like birds the Moas used to be responsible for the di stribution of the seeds. When man came to these Islands the Moas were rapidly hunted to extinction together with a man-sized (!!) Falcon-li ke bird the Moas only natural enemy. No more Moas (and no more Falcon-l ike-bird!) LOTS of people so no more seed distribution no more tre es. Good Growing Julius HTML +More From: desinadora@mail2designer.com To: aroid-l@gizmoworks.com Date: Mon 23 Feb 2009 16:31:52 -0800 Subject: Re: [Aroid-l] Thorns on Aroids Dear All: Here's my two cents - a whole lot more plants than just the Aroids have tho rns in our neotropical forests here in Ecuador and usually it's to defen d themselves from other plants. The spines on many of the other plants and trees are there to discourage competition from growing over them - for exa mple Ceiba pentandra has spines until about its 100th year to discourage colonisation by Philodendrons! (They're often the only smoothly empty pla nts in the forest which makes them very easy to spot....) So any of th e free-standing or vining aroids with spines may have them for the same rea son - so as not to be overgrown by other ferns orchids or lianas. Fo r directional spines I'd look at the size of the plant and its relative habit - downward pointing ones would tend to me to indicate that the plant is trying to protect itself from invadors coming from below while upward -pointing ones say "don't step on me." Lasia is an aquatic as I understand it. I'd bet the spines are particul arly sharp to dissuade wading birds and crocodilids from disturbing the mat as well as to discourage anything that thinks it looks like a tasty sna ck.... It would probably only take one nasty festering thorn wound to keep me away from a plant like that! Then again I grow a number of plants t hat do this to me on a regular basis so maybe I'm not as smart as a hero n! Beth ___ Date: Sun 22 Feb 2009 13:03:14 +0000 From: Subject: [Aroid-l] Thorns on Aroids To: Message-ID: Dear Friends I would think that any thoughts or study on the ''prickles/spines'' on aroi ds would start with the Lasiodeae. Many genera in this group exibit extreme spines one has not lived till o ne has tried to handle or re-pot a plant of Lasia spinosa only to be left w ith the tips of dozens of thorns inbedded in ones hands and fingers to l ater fester and become pustules. The genus Cyrtosperma runs a close second and a specimen of C. macrotum I once had from N. E. Papua-New Guinea was very much like a porcupine to to uch and impossible to handle without resorting to leather gloves. All th e other species in this genus that I can think of are spiney! Podolasia is no better this genus produces a bloom where even the stipe (the structure below the spadix which attaches the spadix to the spathe/ped uncle) is also spiney! Of interest the spines on Podolasia all point upw ards while those on Cyrtosperma all point downwards. The exception is the African genus Lasimorpha its many spines which r un in parallel rows along its petioles are sort of ''crystaline'' and somewhat ''blunt'' so handling has not been a problem for me. A few of the Old World genera are not spiney the Indian Anaphyllum an d the Asian Pycnospatha have at best ''rough'' petioles. The Neotropicis have been kind to us with their Lasioid genera Anaphyllo psis Dracontioides Urospatha all are spineless (though there are a co uple (?) of species (?) of Urospatha in Fr. Guyana with ''roughish'' petiol es) while the genus Dracontium is interesting in that certain species the petioles demonstrate structures which look like spines but are gene rally soft and not ''dangerously'' sharp! I don`t know the origin of these spines in Aroids but they must be a goo d form of defense against browsers and even perching birds etc. I hope this assists our friend Dmitry in his research. Good Growing Julius WPB Florida > From: phymatarum@googlemail.com > To: aroid-l@gizmoworks.com > Date: Fri 20 Feb 2009 14:36:19 +0800 > Subject: Re: [Aroid-l] Thorns at anubiases > > Dear Dmitry > > As I mentioned in my last email we are really not all aware of what ro le > such prickles might play in the aroids. As Tom has also mentioned they oc cur > in Neotropical Homalomena too. The definition of a thorn is an indetermin ate > structure (such as a stem or root) capable of lateral growth through > branching (and even of flowering and bearing leaves in some instances that > have a protective role. Thorns are most commonly found in Rosaceae (e.g. > Crataegus) Fabaceae (notably Gleditschia) and Rhamnaceae (many genera) . > > Very best > > Peter > > ----- Original Message ----- > From: > To: > Sent: Wednesday February 18 2009 8:19 PM > Subject: Re: [Aroid-l] Thorns at anubiases > > > > Dear Peter > > > > This error in terms is probably caused by features of transfer between > > Russian and English. In Russian such epidermal outgrowths are called as > > thorns. Indeed I found in the literature that J. Bogner named them a s > > prickles but he does not write about their role. I have only few > > knowledge about others Aroids. Therefore could You tell me about a r ole > > of such prickles in Anubias? > > > > Best regards > > > > Dmitry Loginov _______________________________________________________________ Get the Free email that has everyone talking at http://www.mail2world.com Unlimited Email Storage – POP3 – Calendar – SMS – Translator – Much More! --_3ac842b0-3ad9-4394-bc6c-0ef1e6f68f8d_ Dear Friends I would think that any thoughts or study on the ''prickles/spines'' on aroi ds would start with the Lasiodeae. Many genera in this group exibit extreme spines one has not lived till o ne has tried to handle or re-pot a plant of Lasia spinosa only to be left w ith the tips of dozens of thorns inbedded in ones hands and fingers to l ater fester and become pustules. The genus Cyrtosperma runs a close second and a specimen of C. macrotum I once had from N. E. Papua-New Guinea was very much like a porcupine to to uch and impossible to handle without resorting to leather gloves. All th e other species in this genus that I can think of are spiney! Podolasia is no better this genus produces a bloom where even the stipe (the structure below the spadix which attaches the spadix to the spathe/ped uncle) is also spiney! Of interest the spines on Podolasia all point upw ards while those on Cyrtosperma all point downwards. The exception is the African genus Lasimorpha its many spines which r un in parallel rows along its petioles are sort of ''crystaline'' and somewhat ''blunt'' so handling has not been a problem for me. A few of the Old World genera are not spiney the Indian Anaphyllum an d the Asian Pycnospatha have at best ''rough'' petioles. The Neotropicis have been kind to us with their Lasioid genera Anaphyllo psis Dracontioides Urospatha all are spineless (though there are a co uple (?) of species (?) of Urospatha in Fr. Guyana with ''roughish'' petiol es) while the genus Dracontium is interesting in that certain species the petioles demonstrate structures which look like spines but are gene rally soft and not ''dangerously'' sharp! I don`t know the origin of these spines in Aroids but they must be a goo d form of defense against browsers and even perching birds etc. I hope this assists our friend Dmitry in his research. Good Growing Julius WPB Florida > From: phymatarum@googlemail.com > To: aroid-l@gizmoworks.com > Date: Fri 20 Feb 2009 14:36:19 +0800 > Subject: Re: [Aroid-l] Thorns at anubiases > > Dear Dmitry > > As I mentioned in my last email we are really not all aware of wh at role > such prickles might play in the aroids. As Tom has also mentioned th ey occur > in Neotropical Homalomena too. The definition of a thorn is an indet erminate > structure (such as a stem or root) capable of lateral growth through > branching (and even of flowering and bearing leaves in some instance s that > have a protective role. Thorns are most commonly found in Rosaceae ( e.g. > Crataegus) Fabaceae (notably Gleditschia) and Rhamnaceae (many ge nera). > > Very best > > Peter > > ----- Original Message ----- > From: <dloginov@ineos.ac.ru> > To: <aroid-l@gizmoworks.com> > Sent: Wednesday February 18 2009 8:19 PM > Subject: Re: [Aroid-l] Thorns at anubiases > > > > Dear Peter > > > > This error in terms is probably caused by features of transfe r between > > Russian and English. In Russian such epidermal outgrowths are called as > > thorns. Indeed I found in the literature that J. Bogner na med them as > > prickles but he does not write about their role. I have on ly few > > knowledge about others Aroids. Therefore could You tell me about a role > > of such prickles in Anubias? > > > > Best regards > > > > Dmitry Loginov _____________________________________ __________________________ Get the Free email that has everyone talking at http://www.mail2world.com Unlimited Email Storage – POP3 – Calendar – SMS – Translator – Much More! --_3ac842b0-3ad9-4394-bc6c-0ef1e6f68f8d_-- --============== 66152309201121410 _______________________________________________ Aroid-L mailing list Aroid-L@www.gizmoworks.com http://www.gizmoworks.com/mailman/listinfo/aroid-l --============== 66152309201121410==--

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