Does anyone know what happened to the plants Wimber (not sure if I got his last named spelled right- don't have the publication on hand) worked on when creating tetraploid paphs? Also, does anyone know the Hybrid and Cultivar names of these plants. Last I heard they are highly sought after plants among breeders due to their high fertility. I wonder if the chromosome behavior among paphs is similar to dendrobiums (ie. all the amphidiploids look like clones, even so their not). Wimber was going publish a paper about this at the 1996 World Orchid Conference, but I do not think he had the chance. Thanks for your help (and corrections if I made mistakes in my spelling).

Here is what I hear of about tetraploid paphs: undesirable for the most part. Their fertility rate does not increase, and the plants grow even slower, and the flowers are even known to be ugly and deformed. IMHO tetraploids are best used for cloning paphiopedilums, but I don't think it is an appropriate breeding use as the plants are too damn slow to flower with most of the current genes. There are a few plants like brachys where this would be viable, but you're playing a waiting game. Personally, for now I would toss them in the trash. Not to mention, you'll probably get infertility or sterile offspring if you breed with the normal 2Ns, resulting in a 3N plant...

Anyone know what the average % of colchinase treated seed actually ends up turning 4n?

Thank you for your responses.

Steve, I think you are correct about what you wrote. Here is a quote from Wimber's publication in Lindleyana 3(4): 177-183, 1988:

"1) In general, the diploid plants in treated flasks and control flasks develop faster than the tetraploid plants of the same age.....3) Tetraploid plants are typically darker green than their diploid counterparts and the tetraploid leaves usually appear to have greater substance. 4) The diploid plants often have more active roots which are longer and thinner than roots of the tetraploid plants taken from the same flask".

However, as far as I know, there are no later publications detailing the description of flower and uniformity among the amphidiploid population. A professor at the University here, who deals with various orchid growers (not specifically paphiopedilums), said these plants are highly sought after and carry a high fertility rate. He very well could be wrong because he does not specialize in paphs. Based on the number of replies to this topic, it seems as though not many people know what happened to these plants. According to this professor, he said the AOS has them in a various collections among private owners and botanical gardens. Who knows.

As for your question Rick, here is another quote from the same source listed above:

"1) White protocorms had the highest average % conversion to tetraploidy, with survival rates above 50% for all treatment durations of 10 days or less. Transformation rates in the 70% range were achieved with treatment times up to 10 days. Longer treatment times reduced both survival and conversion rates. 2) Green protocorms were transformed with less ease, yet survival was excellent for all treatments less than 25 days. Treatment durations up to 10 days gave conversion rates of 50-60%. 3) First leaf stage protocorms also showed high alteration rates up to a 10-day treatment. Unfortunately, their survival rate was 50% or less for all treatment durations...."

If you are confused, I would recomend going to library and getting this publication. It discusses in good detail about the various treatments. Keep in mind, this work is with one or two specific hybrids and does not necessary mean it applies to all paphs.
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Hi. Tetraploid Paphs are usually good breeding plants but this often depends on the specific hybrid. Even though they have 2 complete sets of chromosomes from both parents, subsequent hybridization is not smooth as subsequent hybrids can have conisderable aneuploidy. There is no easy cure for the chromosome count differences between Paph groups. The creation of tetraploids at least allows some subsequent breeding and breeding plants can be selected that are fertile due to more even ploidy. This is difficult but has to be done if one is to move on with hybridization. The chromosome count differences are only part of the problem as repeated DNA content is also different and plays a role in chromosome pairing. As to the slower growth of tetraploids, this was widely claimed for Phalaenopsis but is not true. Most of the larger Phals are tetraploids and grow just as rapidly as do diploids. In fact they may be faster due to selection. The slowest growing Phals are aneuploids and this is probably also true for Paphs.