Nice plant M. Really do like that particular clone. Steve, you bring up an interesting topic. I've always said you could keep recombining those three species in differing proportions to get a wide range of shapes and peristomes. We have an old Victorian hybrid from France, N. Deslogesii, which is described as N. Mixta x N Tiveyi. It is very Mixta-like. A female Mixta was used at the time, I believe it was Mixta 'Sanguinea', which, like the picture above, shows the dominance of the female in these crosses.
Is female dominance real throughout all or the majority of seedlings? Or are these just examples of the cross that tend to favor the mother. I guess I'm skeptical about "female dominance". It just seems to me that people want to believe this, or this is something that makes "sense" to them, and since one, (or a few - I don't really know), person(s) noticed it and wrote about it, everyone else follows suit. Even if the children were split 50/50 between which parent they favored, it would be easy to find examples of female dominance. In order to really showcase my ignorance, i'm gonna get a little deeper into the genetics, (of which I am far from an expert). If females are XX chromosomes and males are XY, (is this even true for plants? - and how do diploids and triploids fit in?), and assuming X and Y chromosomes are different, it seems that:
1) Males can provide more variation to the crosses.
2) No matter what sex the child is it has at least half of the "female" characteristics and some portion of the "female" part of the male. - Hard to believe I got an "A" in H.S. biology with a statement like this. - perhaps this is the reason for "female dominance".
I guess plants have a number of chromosomes and the sex chromosomes are only two out of many. So just for the sake of discussion, I'll leave all that B.S. above. How many chromosomes does Nepenthes have?
And I haven't even delved into the notion that each chromosome is made up of different genes. What exactly differentiates an X chromosome from a Y chromosome anyway? Time to do a little research. Has anyone ever written a book, "Plant genetics for dummies"?
That is the problem when you start applying logical, mathematical reasoning to biology from someone who still thinks the idea of female sperm is funny.
A day without Nepenthes is like a day without sunshine! -- steve
Post by Rainforest Carnivores on Jul 8, 2006 23:20:25 GMT 7
The female dominance is an interesting topic. For the most part, I believe its true, but on some species, no matter what if they used males, it would appear to win over even the female characteristics.
The very dominant species I have seen so far include N. gracilis, campanulata, albomarginata, and I'm sure many others. N. Cincta ( N. north x albomarginata) resembles almost entirely albo, while in Trichocarpa (N. amp x gracilis) the amp gene seems to be reduced. And EP's N. truncata x campanulata, campanulata thin peristome pitchers seems to predominate.
N. lowii shows a strong dominance when comparing N. lowii x ventricosa and (N. Briggsiana) N. ventricosa x lowii. Both look very close to each other, thus N. lowii seems to be dominant.
Even N. Cincta when used in a second generation breeding still becomes the dominant characteristic in the cross. (example is N. ventricosa red-squat x Cincta) where N. Cincta dominates in plant form, pitcher shape and coloration.
Another second generation hybrid that clearly shows dominance is N. bicalcarata x trichocarpa. The growth habit is definitely Trichocarpa, even down to the smallish speckled pitchers of N. trichocarpa. But even so, N. bical even reduces greatly when crossed with gracilis, making even a smaller thin vine with smaller pitchers!
Geoff Mansell wrote an article on hybrids, he mentions female dominance. I think he would be the expert on this topic. He even said, for example rafflesiana x sibuyanensis grows as a lowlander while the reciprocal sibuyanensis x raff will grow in intermediate/highland conditions. The pod parent will also influence all other aspects of the plant. Who here thinks that ventricosa x truncata looks the same as truncata x ventricosa? Based on a 50:50 concept, the results of both crosses should be the same... but they're not.
Yeah, Geoff would know about female dominance. But, just for the sake of discussion, I don't see how any two crosses would look the same with different parents when even siblings of the same cross look different. With an almost infinite number of gene combinations and even gene crossover going on, I bet you can get different looking plants from two different crossings using the same parents. I must admit to not having seen a lot of different clones or grexes between different pairings of ventricosa and truncata. So are you saying that many different grexes of truncata x ventricosa share more in common with each other than grexes of the reverse cross?
Could it be possible that the children get their environmental tendency from the environment in which the seeds were generated? I'm not saying if you can get some bical seed to develop in a highland environment that you will end up with highland bical, but you may end up with a less lowland bical. One approaching intermediate conditions.
A day without Nepenthes is like a day without sunshine! -- steve
The environmental factors don't determine the physical features of a hybrid, the genetics do. As for temp tolerance in hybrids, the Mansells had the same evironment for the cross and reciprocal of raff x sibuy, but one was lowland growing and the other was not. You can find out which bicals are more tolerant of highland conditions, and keep crossing them to each other to create "cold tolerant" bicals ... like Steve Stewart did. But, no, the growing conditions don't determine the outcome of the seedlings (the plants will either tolerate it or die).
The amp like pitcher is N. 'Ron Determann' (ampullaria x alata)
We've re-potted that plant into a huge pot and it has too many pitchers to count!
Thanks twoton for the pronounciation - we always questioned what would be correct.
plantguyty1: I'm looking for pollen.
Dec 31, 2016 23:50:46 GMT 7
fredp: I'm trying to add a PDF file to a new thread but it doesn't seem to work thru the "Add Attachment" button. Can someone help?
Jan 8, 2017 0:08:27 GMT 7
plantguyty1: Does anybody need pollen? I have N. Miranda it's the first time it flowered for me so I do not know if its sterile or a good candidate. Is there anybody with an active female that would like to give my pollen a shot?
Feb 19, 2017 1:19:37 GMT 7
siravi: im looking for seeds, anyone?
Mar 15, 2017 13:41:04 GMT 7
samu0945: I'm looking for N. Aristolochioides
Apr 2, 2017 8:48:30 GMT 7
thatoneplantboi: Hey guys, I'm new to growing nepenthes, I'm getting a mini indoor greenhouse to grow them in. What kind of light should I use for them? Also, if you could provide a link to a product, it would be very much appreciated
Oct 5, 2017 10:16:29 GMT 7
borneo: Yes, they work superbly. But you don't need expensive lights, cheap ones work well too.
Sept 2, 2018 14:34:57 GMT 7
mylesg: i havent checked in here for a while, why does it seem all the CP forums have lost their once strong activity? the trade/sale section used to be so active and now its a ghost town. where is everybody hanging out these days for a strong online CP community?
Dec 9, 2018 3:15:01 GMT 7
mylesg: Happy holidays to everyone out there!
Dec 26, 2018 0:23:13 GMT 7