Hello all of you. Hope you are all well and looking forward to the holiday season.
I have a question.
Do any of you have both the dip. And tet conversion of the same cultivar and do each perform in their own right.
Why I ask is I have a few conversions but they do not perform well. Then again I do not have the original dip. So I have nothing to compare them to.
Thanks for any imput.

I had the dip Inspired Word, and still have the TET conversion. The dip grew well, the TET grows Slow making one fan/year. Dip Connie Burton grew well for me, the TET conversion is really bad. I have lost two of them. At an average cost of $200.00 each, I cannot afford to continue losses like that. In general, TET conversions are not as vigorous as the Dip they were converted from. I think the traumatic process of converting them screws up the genetics---in particular their ability to withstand extremes of temperature.

I have both versions of Rainbow Radiance. 1st year for Tet version to bloom, EDIT{fertility [pod] seems to be good...seedlings sprouted... }CLOSE EDIT hoping it passes on polychrome. Also have both versions of Cosmic Kaleidoscope. The Tet version hasn't bloomed yet but the plant is doing ok so far.

I have the dip and tet version of Lillian's Thin Ice and their performance is indistinguishable from one another in almost every way, to my surprise. Pollen fertility is good with the dip version; less successful with the tet. Pods are equally challenging to set on both (read: nope!).

I had pretty dismal results from purchasing and using tet conversions, and Karen at Floyd Cove had a really good suggestion that I've put into use ever since -- I get a daylily instead that is a seedling from that tet conversion (usually an introduction), one that the hybridizer says is fertile and has the characteristics I'm looking for -- and it's worked really well for me.

I have the diploid and tetraploid version of 'Siloam Virginia Henson' (SVH). I would rate them about the same. But one qualifier, that applies to all tetraploid conversions. Most daylily tetraploid conversions are not complete - meaning some parts of the original converted daylily are tetraploid and some parts are diploid. Just like green/white leaf variegation is often lost in daylilies with the passage of time and increase of the daylily so can the tetraploid tissues in some converted daylilies be lost with the passage of time and increase of the converted daylily. That means some tetraploid daylily conversions may be diploids not tetraploids. Unless I look at the pollen of the tetraploid SVH under a microscope and compare it to the pollen of the diploid SVH I cannot be certain that the tetraploid SVH is actually tetraploid.

Oh, wow. So a conversion can sort of do a slo-mo fail, reverting back to the diploid state, in part or even potentially completely? So, it could be POSSIBLE that my dip and tet Lillian's Thin Ice act the same because they are both acting as dips? Fred, I'm gonna give you the benefit of the doubt here.

When we use a seedling of the converted dip, say Tet RFK, are the genes are more stable and fertility more reliable? That's interesting advice, Betty. That's how I tend to roll. So, if I use, say, Dancing Flamingo (Cutting Loose x Tet RFK) as a parent, I may have better success with the crosses than directly working with Tet RFK? (Assuming it's a good parent.) Anyway, it's often cheaper to buy a kid than buying an expensive in-demand conversion.

Hembrain said:Oh, wow. So a conversion can sort of do a slo-mo fail, reverting back to the diploid state, in part or even potentially completely?

Yes, only complete conversions are safe from reverting back to being diploid. In the early years of tetraploid conversions the advice to anyone thinking of buying a converted plant was to do so only if the seller had checked the plant recently for its tetraploidy status - by examining pollen or stomata with a microscope.
Also, Arisumi, a plant geneticist published his research on converting diploid daylilies to tetraploids. He did something specifically to reduce the possibility of losing the tetraploidy when he treated his plants. I do not know, but I suspect that those who convert daylilies nowadays do not do what he did.
Nowadays crowns with one fan of leaves are treated. The main growing point is treated after the leaves are cut down severely. Arisumi did that. But once the treated growing point started growing again after the treatment was done, he removed all the rest of the crown around the growing point and forced what was left to sprout new roots. By removing all the rest of the crown Arisumi removed all other untreated (diploid) growing points on the crown. If that is not done then over time, when the treated plant increases from one fan to many fans some of those untreated growing points may sprout and produce diploid fans. That can happen even when the treated fan produced a complete tetraploid.
The end result is that over time there are two ways that a converted tetraploid daylily may revert back to diploid.
1) It was only a partial conversion and the diploid parts manage to replace the tetraploid parts
2) diploid growing points were not removed and they later sprout to produce diploid fans in the clump so that it becomes a clump of both diploid and tetraploid fans.

So, it could be POSSIBLE that my dip and tet Lillian's Thin Ice act the same because they are both acting as dips?

Yes, that could be possible. It is important to understand that the more years have passed (the older the tetraploid conversion becomes) the more likely the clump is no longer all tetraploid - if it was not a complete tetraploid conversion originally.

When we use a seedling of the converted dip, say Tet RFK, are the genes are more stable and fertility more reliable?

Only the treated plant itself can possibly revert. Its seedlings are completely stable. Their fertility is normally better than that of their converted parent. The hybridizer who made the crosses using the converted parent would know the fertility of the seedlings that had been selected. Their fertility may or may not be the same as the general (non-conversion) tetraploid population. To know that would require a special analysis.

So, if I use, say, Dancing Flamingo (Cutting Loose x Tet RFK) as a parent, I may have better success with the crosses than directly working with Tet RFK?

As long as better success means a higher percentage of pollinations successfully set pods and produce seeds that is generally what to expect. Specifically, that depends on the actual fertility of the Tet RFK conversion and of 'Dancing Flamingo'.

I honestly think that just about all of my tet conversions had already reverted back to diploids by the time I tried them because I just couldn't get anything to take when I used their pollen on tetraploids. Of course there could have been other reasons, but after trying several of them for more than one year that was the feeling I ended up with; and I was delighted to switch to other people's seedlings and have much better results. But then, this is just a hobby for me and I'm not really a serious hybridizer...

I figured tet Rainbow Radiance must be stable since it has been around for 20+ years having a child registered in 2000 and as late as 2015. Set pods both ways on tet crosses. The only registered "kids" were pollen based so we'll see in a couple years.

Super-interesting! Thanks, Maurice, for the elaboration!

Do I remember that a (successful, stable) tet version of a dip is generally more likely to be pollen-fertile than pod fertile, or at least more pollen-successful?

And how frustrating, Betty, that this has not been your experience. (Good attitude, though.) A caution to those with big plans and high hopes, ready to part with big bucks for converted material. But pros may just call that the cost of doing business.

Hembrain said:Do I remember that a (successful, stable) tet version of a dip is generally more likely to be pollen-fertile than pod fertile, or at least more pollen-successful?

Theoretically, based on the biology, the pod and pollen fertility should be approximately the same for a successful complete conversion. In practice that may or may not be the case and it may be different for each species - I would need to do a survey of the scientific reports to determine that. However, I think that the recommendation from those who do the daylily conversions is that it is best to use a converted plant as the pollen parent - unless the conversion is known, by microscopic examination to be a complete conversion.

Stamile wrote an article in the Daylily Journal Volume 45 Issue 3 Fall 1990 starting on page 242 titled From Diploid to Tetraploid.
In it he wrote,
"The technique described is successful in converting only 20% of the plants
treated to full tetraploids. However, all is not lost, since almost 60% of the
treated plants are part tetraploid. These chimeras produce both diploid and
tetraploid pollen grains and can be used on known tetraploids to produce seed."

He also wrote,
"Since all chimeras which have any diploid tissue in Layers 1 and 2
produce both diploid and tetraploid ovules and pollen, they should be used only
as pollen parents unless one is skilled in the use of the microscope to identify
tetraploid tissue. Otherwise, both tetraploid and diploid seed may result from
their use as pod parents."

And he wrote,
"Be wary of growths coming from under the crown. These are probably from dormant
lateral buds. Since these buds were not in active growth when the colchicine was
applied, they are probably diploid. Occasionally, they too can be affected by the colchicine
but this rare."

Since I think that most modern daylily hybridizers do not do what Arisumi did (remove all the crown tissue that could produce new diploid fans from those buds that Stamile mentioned) is why I think that nearly every tet conversion will be basically diploid at some time as they grow and increase.

And Stamile wrote
"Don't use your treated plants as a pod parent unless you become skilled with
a microscope to check (a) length of pollen grains for indication of Layer 2
conversion, and (b) length of the stomata guard cells for indication of Layer 1
conversion (diploid guard cell length x = 32μ, tetraploid guard cell length x =
43μ). Most treated plants are chimeras which means they have both tetraploid
and diploid tissues. It is easy to fertilize the diploid tissue and then you will have
diploid seeds. Many modern daylily hybrids are nocturnal or open very early in
the morning. These daylilies can be pollinated by night insects long before you
or the bees arise. Highly fertile diploid tissue can be easily self- or cross-pollinated
by such insects. Unless you are willing to open up your flowers the day
before and foil-cap the sigma until you pollinate it and then recap it, don't use
chimeras as pod parents.

Use your chimeral pollen on known tetraploids. All the seedlings, with the
rare exception of a generally sterile triploid or aneuploid, will be true tetraploid
seedlings."

Thank you all. So much more than I ever expected. Thanks to yall I am more educated than I was before.

Very informative and interesting. I will be keeping an eye on my T. Rose F. Kennedy.
Maurice thanks for keeping us in the know