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Post by rsivertsen on Apr 21, 2007 22:31:17 GMT
Gus,
I'm quite familiar with gene pools and actually get a little upset when I hear rumors that seed of N. lowii harvested from Murid, Trus-madi, or elsewhere get deliberately released onto Kinabalu, which may contaminate a very unique gene pool of N. lowii on Kinabalu. To that extent, yes, I’m a purist. I would like to see these gene pools remain true to their location.
Getting back to N. ventricosa, the type specimens recorded for the species, according to John Turnbull, have this peristome that ends without them coming together, and rising up towards the lid, and is also distinctly flat, and horizontal, unlike the more oblique angles we see in other species; the leaf shape and length is also distinctly different; however, the color does vary, and in younger plants they even have the red color on the upper part of the inside wall of the pitcher, also, the photos that John Turnbull brought back showed a population of these foot long N. ventricosa pitchers (growing epiphytically, and hanging from a tree), which were blood red in color. The recorded type specimens in the various herbariums and research records and are the definitive word on the species. It’s how the science of taxonomic botany works.
The only true specimen of that N. ventricosa that is in cultivation seems to be a porcelain color pitcher, but it can turn a dark pink in sunlight, but without any spotting. To my knowledge, no one has been able to get it to produce a flower in the last 30 years or more, (not even Longwood Gardens, where I got it, and before that, Kew Gardens, UK), so we don't even know what gender it is! After over 10 years, with a 6 foot stem, it refuses to produce a flower. I have only a small rooted cutting of it now, and it is a very slow grower.
You are aware that some gene pools actually do get contaminated with another species, even though that other species may no longer exist anywhere near the site, or at all for that matter. I have personally observed this in Sarracenia alata and S. leuco, both species growing within the same site. Specimens that I collected, that I was fairly sure were true species, all produced cream colored pitchers the following season, indicating that they were all hybrids; also hybrids into S. purpurea where hours long search found not even a single S. purp.
Human interferences such as lumbering and development create significant disturbances to the environment, and some may actually deliberately introduce new species for various reasons into a site, or allowing lost and wayward pollinators into another gene pool altogether.
I am well aware of what can be done in artificial breeding programs, and I have speculated many times that with those species that grow rapidly, produce flowers readily, one can conceivably produce something that looks very different within a few generations, especially with those plants that have a high propensity for producing “sports”.
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Post by agustinfranco on Apr 22, 2007 0:58:05 GMT
Dear Mr Sivertsen:
Nepenthes Species, in general, maintain a certain set of characteristics which are obviously passed on to the next generation, but lack of variation within a species is definitely detrimental for the survival of the same. The assumption that the set of genetic characteristics must be strictly maintained for the species to be healthy may be mistaken. We need a degree of genetic exchange between two or more plant populations from time to time for these to be fit. I am not aware that there are a wide range of species co existing with ventricosa, but if they did, let's say N. alata, wouldn't then we have more ventratas around?. Perhaps the original population of ventricosas absorbed the genes from species on the verge of extinction and make these their own. The only way to prove this, without going to gene sequencing at this stage, because of the complex numbers of chromosomes involved, which in turn becomes a cumbersome task is to go there to those places where the alledged hybrids are, if we find other new or well known species, i'll accept your hypothesis, but if we don't, then those new genes are part of a new ventricosa population!. Let's not forget that new species can be created from stable hybrid populations which gain a foothold in the wild displacing unfit old species. Now there is what we call mutations, but these would take much longer to have an effect on the genotypic and phenotypic characteristics of an evolving species.
I think the problem may lie in the definition of a species. If we commonly accept the fact that species is a species where the set of genetic characteristics must be passed on its totality from the moment it became a species and these will never change or they are not allow to change, we are dooming all neps on the planet. I am optimistic that even villosas having a very strict habitat must have genes not commonly expressed ready for adaptation when their habitat suddenly changes. As a matter of fact, we come to the next point, how do we know that all their genetic traits are expressed at once and perhaps these skip generations. The possibilities are endless.
Gus
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Clint
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Post by Clint on Apr 22, 2007 1:47:35 GMT
I think, perhaps if this ever did happen, we'd have much controversy as to when a hybrid becomes a species. For example if one or both parents go extinct or if the hybrid goes on and continues to evolve over time. It's always the splitters versus the lumpers
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Post by agustinfranco on Apr 22, 2007 2:20:17 GMT
Hi there:
Another problem occurs when it happens, there are no extinct parents to show us the story.
Actually, i'd like to find out whether the so called hookeriana hasn't become a species yet?. Considering that the hybrids in the wild are very rare, maybe these are species in the making. Has anyone actually crossed two hookerianas to see whether the progeny go back to their original parents?
Gus
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matti
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Post by matti on Apr 22, 2007 3:28:56 GMT
Gus, I'm quite familiar with gene pools and actually get a little upset when I hear rumors that seed of N. lowii harvested from Murid, Trus-madi, or elsewhere get deliberately released onto Kinabalu, which may contaminate a very unique gene pool of N. lowii on Kinabalu. To that extent, yes, I’m a purist. I would like to see these gene pools remain true to their location. You say this yet you openly discuss releasing Aldrovanda into the wild were they are not found natrully, can you justify this?.
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Post by ep on Apr 22, 2007 4:18:41 GMT
Hi All. It is good to see this forum up and running. Also what a great topic to start. N.ventricosa is a much maligned species that is often just tossed to the back of collections. They are fascinating plants and in what we have seen and bred would have the esteem of N.lowii, which they are like, worldwide if they were not so easily grown or commonly known. Gus just brought my attention to this N.ventricosa controversy and also a couple of incorrect statements being made here. So for some clarity into the situation here is some more input. To start, we have what you are calling the porcelain N.ventricosa, 2 forms. They are listed as N.ventricosa(c) and (d) in our catalogue. In our experience and conditions, they are somewhat different to grow and pitcher than the known typical forms, being slower and more specific(highland) in their requirements. They are both females that have taken years to flower. The pitchers are quite hard like N.lowii and the differences between the 2 forms we have is the internal pitcher colour and peristome colour. One maintains an all white interior which does get a pink flush as the pitcher ages with a pink/red peristome, type (d). The other darkens internally with age to a dark maroon/purple with a purple/black peristome. I brought the subject up a few years ago with Ch'ien Lee when he visited and also suggested that these 2 forms were actually the type material and all others were, IMO, another species. Like N.burkei in relation, close but not N.ventricosa. He tended to agree. At this time though, no new work has been done on classification of this species. To say the other forms are hybrids is not true. We have done a lot of breeding and they breed true to 'type'. Although, in the context of this discussion, the plants I have seen and we have may not be type N.ventricosa , they are true species or species variants. The origin of most of our N.ventricosa plants goes back to a Filipino collector, Peter Sang, who I knew many years ago. Peter lived in Brisbane and made frequent visits to the Philippines where he brought back many plants. After Peter died his collection was donated to the botanical gardens. At that time their room was inadequate and we received the plants. Interestingly, the N.ventricosa(d) form was labeled 'Ex-Japan' when we received it! As I previously stated, we have since then done a lot of breeding with this species both in hybridization and along the species line. All our plants are true to type and meticulous records are kept. To say that our red N.ventricosas are hybrids is erroneous too, in fact our new ones are close to purple! There is an occasional sport and if worthy these are used in breeding and noted. I feel it would definitely be interesting to do some field work on this(these) species to see what is actually around. BTW. nic, I would be interested to know where you have seen a N.ventricosa supplied by us with wings. Hope you enjoy the pics. Geoff
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Post by agustinfranco on Apr 22, 2007 5:00:08 GMT
Thanks Geoff for your historical data recollection. It' d be interesting to see why there is a higher degree of variation on genotypical and phenotypical characteristics, since you sell the largest range of ventricosas variants IMO.
Gus
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matti
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Post by matti on Apr 22, 2007 6:00:02 GMT
G'day Geoff, thoes are some nice plants, I was wondering what your Greenhouse conditions are like if I may ask?. I have a couple of your ventricosa plants like the one posted and they are BRILLIANT. ;D
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Post by rsivertsen on Apr 22, 2007 14:50:10 GMT
Geoff,
Thanks for the input and glad to know that someone has finally got it to flower! The curators at Longwood Gardens sent some Nepenthes plants to Japanese collectors back in the early ‘70s. The suggestion that the red forms were of hybrid origin came from several Japanese authorities during the mid ‘70s and early ‘80s, (pers. com.), who cited the similarities to N. alata red forms that are also found in the same general area, and made several visits to these places. John Turnbull also considered these red forms "suspicious at best". The pitchers of N. ventricosa are nearly woody like N. lowii, while the smaller red forms are softer and a bit brittle. I hope you have both male and female plants of this plant now! Perhaps someone should make a case for identifying these red forms as another species. Thanks for the images that show the size and the peristome of N. ventricosa too! Well done! I’m curious to see some of the “sports” you have come up from seed!
Matti,
The Aldrovanda I have in a small private pond does NOT threaten any other gene pool of Aldrovanda. In trying to keep an “open mind”, it just may occupy a vacant niche here, (as rare as that may be), and it was my intention just observe them in a natural setting. The site was already an eyesore, going through cycles of algae blooms and littered with refuse, debris and junk. There is both duckweed and a water lily that would quickly overwhelm and drive the Aldrovanda into oblivion if I didn’t clear them out several times to allow the Aldrovanda to grow. I am convinced now that Aldrovanda are intimately linked to the other life forms in their habitat in a complex symbiotic community involving large monocot plants that rapidly absorb nitrogenous matter, and release large amounts of CO2, along with the population density of zooplankton on which it feeds; it is the ONLY plant that can capture the largest stages of mosquito larvae. Without the presence of it’s required constituents, it quickly goes into decline.
Gus,
Getting back to Nepenthes, N. villosa, along with N. rajah, and N. burgidgea are lithophytes, only found growing on exposed ultra basic rocks, mostly serpentine, which records the most endemic species of plants; limestone runs a close second (N. northiana is found growingly exclusively on limestone cliffs). In cultivation, they can be grown on, and in other materials. Interestingly, I have found Darlingtonia growing on ultra basic rocks, and in small mountainous streams in running water, sometimes so small, it’s almost unnoticeable. Populations of N. villosa seem fairly uniform, not many differences in the plants, while N. rajah and N. burbidgea do show some variability.
Some Nepenthes hybrids seem to demonstrate more vigor than others, and hybrids are NOT rare in Nepenthes or Sarracenia; I was schooled in the classic principals of Botany, which does teach that hybrids are very rare, and for the most part this is true, and they are also usually sterile too (such as Drosera and Pinguicula hybrids) but NOT Nepenthes or Sarracenia. They also don’t seem to pan out according to Mendelian theories of genetics either when crossed with each other or back-crossed.
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Post by agustinfranco on Apr 23, 2007 9:40:06 GMT
Hi Mr. Sivertsen:
Thanks again for your reply. I do believe there is a misconception when it comes to hybrid habitats. The fact that they exist, there is no doubt about, but based on the well established hybrids around like hookerianasor macfarlanei X sanguineas or macfarlenei X ramispinas, one does not find a large range of these, because the species seedlings almost always take over the space available for these to grow in the wild. In order for a hybrid to fluorish in nature, it has to really compete with well established species. what nobody has done so far is to cross a male with a female of these well established hybrids F1 see whether you obtain siblings F2 with characteristics similar if not identical to P1 or original parent species cross.
I get the feeling that many of these crosses will just produce more of the so called hybrids. If this is the case, would these then have become New species?
Gus
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Post by rsivertsen on Apr 23, 2007 14:29:03 GMT
It's still a mystery why some natural hybrids seem to exhibit their hybrid vigor, while others do not. N. ramispina, N. sanguinea and N. macfarlanei all grow together in several areas in the Genting Highlands of the Malaysian Penn. The colors of both N. sangunea and N. macfarlanei are both very different than those same species in the Cameron Highlands where N. ramispina does NOT occur. In Trus-Madi, N. macrophylla has some characteristics of N. edwardsiana (peristome) while the large vaulted lid is similar to N. lowii, and may be a hybrid colony of the two. Curiously, N. edwardsiana has yet to be found on Trus-Madi, to my knowledge.
Nepenthes seedlings have a very high “infant mortality“ rate in the wild, and those hybrids that do not have the features that allow it to out compete other seedling may fail to thrive. Other plants seem to go on to produce complex back-crosses with one, or both of the other parent species, and ultimately create a contaminated gene pool population; which does occur in Sarracenia species; I have seen this myself, in some areas, where undecipherable hybrids out number what appears to be true species.
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Post by srduggins on Apr 25, 2007 22:12:25 GMT
Fascinating discussion, and I'm glad to see everyone keeping things civil, (for the most part). After hearing the latest discussion, I discover that I am already growing this porcelain form, (clone (c) from EP). My conditions are closer to highland conditions and in the winter are pretty extreme highland. The non-type ventricosa stops pitchering in the winter for me and it is interesting to note that the clone (c) did pitcher in the winter. Not surprising, given it is more highland in nature.
This situation could become quite messy with all the "ventricosa" in circulation, if the non-type is eventually separated into a different species, (or hybrid). All those plants and hybrids in cultivation would need to be re-named, as would EPs ventricosa clones, (now hybrid), that were produced with clones (c) or (d), but they would retain ventricosa in the hybrid name. And what would we call ventrata? Especially if non-type ventricosa is determined to be a back cross to the type ventricosa from a wild ventrata hybrid. Has EP ever crossed one of their type ventricosas with a red alata to see if their progeny looks like the non-type ventricosa?
Thanks for all the enlightenment.
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Post by agustinfranco on Apr 26, 2007 21:10:59 GMT
Hi Steve;
What it's most impressing from EP photos is that most of the clones shown here managed to maintain the ventricose waist, if i may put it this way, and the peristome flat as the porcelain clone. With the exception of the last photo in which the pitchers look elongated and may be a complex hybrid perhaps, the rest of the photos are IMO several types of ventricosa.
Assuming for one moment that the red clones are hybrids, let's say, for the sake of argument: complex hybridization must have taken place to adopt the red colour and maintain the ventricosa characteristics. Since these events must have taken place over a period of 20-30 years perhaps, IMO, these may be new variants of ventricosa: as simple as that.
Gus
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Post by rsivertsen on Apr 26, 2007 22:30:41 GMT
Gus, and all, I never said that all pure N. ventricosa were all pale, or a porcelain color, nor that all red forms were hybrids, only that the one true species of N. ventricosa that I knew of, in cultivation, was this clone that was this porcelain color; I did mention that I observed several photos from John Turnbull of a stand of N. ventricosa that showed dark red pitchers, with pitchers that looked like they were about a foot long. Color alone, is not a botanically significant enough feature to warrant a new species status, but the combination of the petiole, leaf shape, and length, peristome shape, and angle, and especially the inflorescence, the size and shape of the raceme/panicle (one flower or more than one per branch), are all far more significant features for taxonomic purposes.
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Post by srduggins on Apr 26, 2007 23:15:18 GMT
Yeah, it can get a little confusing wading through all this info. What I look for now is the angle on the peristome. I noticed the EP bred pics seem to retain this except for the last photo. Since both of their type ventricosa clones are female, they must have bred them with non-type ventricosa clones and ended up with the same horizontal peristome. I wonder if they are selecting among the seedlings for flat peristome and constricted waist as these would seem to be desireable qualities for horticultural purposes. I wonder how the other determining factors: petiole, leaf shape and length, look in these home grown clones. I'll have to reread these posts to remember how these compare within the two varieties. I wonder if EP has any pics of the inflorescence on their two type ventricosa clones. Seems like that would be very important in determing the taxonomic classification. edit: I just noticed a similarity between ventricosa clone (d) and alata clone (f). Note the bulbous base and funnel shaped trunk on both of these plants. So, perhaps they share some common ancestry. Does clone (f) come from Luzon too? alata clone(f)
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