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Breeding/selecting
- Thread starter zappafan
- Start date
NickHubbell
It’s a trap!
I find such selections to be a very long process. In 2001 and again in 2002, I selfed 'Red Dragon', selfed 'Jaws', crossed 'Red Dragon' x 'Jaws', and 'Jaws' x 'Red Dragon'. I have several hundred seedlings, but they are still too small to make any judgement about. Perhaps by the end of this summer, I will be able to see some significant differences in the plants -- but perhaps not. I find the process to be fun, nevertheless.
Concerning how long it took my seed to germinate. I sowed several thousand seed directly on milled sphagnum peat, but I did not stratify any of the seed. Some seeds began to germinate within about 3 weeks, others continued to germinate throughout the summer and fall, and now there are still seeds germinating this spring after a winter in an unheated greenhouse (natural stratification). If you want more uniform timing of germination, it is best to stratify the seed.
Concerning how long it took my seed to germinate. I sowed several thousand seed directly on milled sphagnum peat, but I did not stratify any of the seed. Some seeds began to germinate within about 3 weeks, others continued to germinate throughout the summer and fall, and now there are still seeds germinating this spring after a winter in an unheated greenhouse (natural stratification). If you want more uniform timing of germination, it is best to stratify the seed.
As far as the stratification of seed, I stratified some seed at one point in damp paper towel in a plastic bag, about three weeks later I looked at it, D. californica seed for some reason left a yellow mark above one seed in the paper, and a D. muscipula seed left a red stain. I'm guessing that this isn't really a good thing for the seed, just really odd. I would definately advise fungicides with just about anything that's going to be in a refridgerator for a period of time. Well...unless it's fungus that you're putting in there.
NickHubbell
It’s a trap!
I used pollen from another flower on the same plant. I find it difficult to pollinate the same flower with itself because the stigma is receptive several days after the anthers are ripe. Using another flower that has recently opened on the same plant (or clone) to pollinate one that has been opened for several days makes for a much better success and a higher number of seeds, with exactly the same genetics you would get if you used the same flower to pollinate itself.
Jmenprkr,
It takes from 3 weeks to several months for the seed to germinate. The first "leaves" are 2 cotyledons without traps. A few weeks later, the first true leaves with traps will emerge. The traps will be about 1 mm in size and will close when stimulated. Consequently, they can now catch and "eat" very small bugs. The traps will get progressively larger and by the end of the summer may be perhaps 3 mm. The second year, you may get traps between 5 and 10 mm. The third year, some of your seedlings may flower and the traps may be larger than 10 mm. If you are in a hurry, buy a mature plant.
At least, the above has been my experience in growing VFTs in an unheated greenhouse for several decades. Growing conditions can affect the rate of growth greatly, but growing VFTs from seed is a lengthy process. The commercial growers can "push" the plants by providing ideal growing conditions. Most of us, however, have less than ideal conditions and our plants develop more slowly.
It takes from 3 weeks to several months for the seed to germinate. The first "leaves" are 2 cotyledons without traps. A few weeks later, the first true leaves with traps will emerge. The traps will be about 1 mm in size and will close when stimulated. Consequently, they can now catch and "eat" very small bugs. The traps will get progressively larger and by the end of the summer may be perhaps 3 mm. The second year, you may get traps between 5 and 10 mm. The third year, some of your seedlings may flower and the traps may be larger than 10 mm. If you are in a hurry, buy a mature plant.
At least, the above has been my experience in growing VFTs in an unheated greenhouse for several decades. Growing conditions can affect the rate of growth greatly, but growing VFTs from seed is a lengthy process. The commercial growers can "push" the plants by providing ideal growing conditions. Most of us, however, have less than ideal conditions and our plants develop more slowly.
Zappafan, what you are describing is indeed recombination. It is due to the fact that organisms often (usually) have two copies of the "same" gene - one from each parent. If these two copies are identical, the organism is said to be homozygous for that gene. However, if the two copies are "different", then the organism is heterozygous for that gene, and when it produces gametes, there is a (theoretically) 50:50 chance that each offspring will get one or the other copy.
If you've heard of "dominant" or "recessive" traits, it is referring to the behaviour of the two copies of the same gene. A dominant trait is one that is expressed in the organism even if there are two different versions of the gene, a recessive trait won't be expressed unless BOTH copies of the gene are the same.
A good example of this is albanism. Typically, this is a recessive trait/mutation, and a plant must be homozygous in the anthocyanin-free gene to be albino (a simplified case, of course).
So, to get back to your original question. Say the plant in question is heterozygous in three genes. That means that there is a 0.5 x 0.5 x 0.5 (x 2) = 50% probability that the offspring will have the same genetic makeup as the parent. Ok, i'm pretty sure i just did that probability wrong (always was a weakness), but you get the idea (i hope).
This is why it's important to have multiple clones of a plant in existence - to make sure that all the possible genes are represented. Consider that once a gene becomes homozygous in an organism, there is no way its offspring can have a variation in that gene except through a random mutation.
Is that clear?
All of that is covered, in a rather more gradual manner, in most Jr. High Bio courses, but most of us (me included) forget until we hear it again in high school, college, etc. It's the Mendel and the peas experiments, if that rings a bell (no, that's pavlov
j/k).
Here's a more graphic example:
R = dominant gene for flower coloration (red flowers)
r = recessive gene for flower coloration (colorless (white) flowers)
Parent plant:
Rr (one copy of each, heterozygous).
If there are four offspring:
RR Rr Rr rr ==> 50 % chance that offspring will have same gene makeup as parent.
The above is a probability, and is of course subject to variation in real life and small samples.
So, in this example, the parent had red flowers (R is dominant), one of the offspring had white flowers (homozygous for the recessive trait), and three had red flowers. Of those three, one would never give white-flowered offspring if selfed. In that way, genetic variation can be "lost" in small populations.
If you've heard of "dominant" or "recessive" traits, it is referring to the behaviour of the two copies of the same gene. A dominant trait is one that is expressed in the organism even if there are two different versions of the gene, a recessive trait won't be expressed unless BOTH copies of the gene are the same.
A good example of this is albanism. Typically, this is a recessive trait/mutation, and a plant must be homozygous in the anthocyanin-free gene to be albino (a simplified case, of course).
So, to get back to your original question. Say the plant in question is heterozygous in three genes. That means that there is a 0.5 x 0.5 x 0.5 (x 2) = 50% probability that the offspring will have the same genetic makeup as the parent. Ok, i'm pretty sure i just did that probability wrong (always was a weakness), but you get the idea (i hope).
This is why it's important to have multiple clones of a plant in existence - to make sure that all the possible genes are represented. Consider that once a gene becomes homozygous in an organism, there is no way its offspring can have a variation in that gene except through a random mutation.
Is that clear?
All of that is covered, in a rather more gradual manner, in most Jr. High Bio courses, but most of us (me included) forget until we hear it again in high school, college, etc. It's the Mendel and the peas experiments, if that rings a bell (no, that's pavlov
Here's a more graphic example:
R = dominant gene for flower coloration (red flowers)
r = recessive gene for flower coloration (colorless (white) flowers)
Parent plant:
Rr (one copy of each, heterozygous).
If there are four offspring:
RR Rr Rr rr ==> 50 % chance that offspring will have same gene makeup as parent.
The above is a probability, and is of course subject to variation in real life and small samples.
So, in this example, the parent had red flowers (R is dominant), one of the offspring had white flowers (homozygous for the recessive trait), and three had red flowers. Of those three, one would never give white-flowered offspring if selfed. In that way, genetic variation can be "lost" in small populations.
