admmad said:Arisumi, a geneticist, did a large experiment trying dip/tet crosses.
He tried with 82 different diploids and 75 different tetraploid parents. There were 400 different diploid - tetraploid combinations.
The total number of pollinations was 1,607.
{...}
Of the 400 combinations of crosses only 24 produced any viable seedlings. Fifteen of those were tet x dip and nine were dip x tet.
Only four of the 24 combinations produced more than one seedling (three produced two seedlings and one produced three seedlings); they were from tet x dip crosses.
There was a tendency for the ability to successfully cross (tet x dip) to be inherited, as a large number of successful crosses involved certain cultivars in the ancestry of the parents.
CaliFlowers said:
Did Arisumi record any information regarding the ploidy of the seedlings from these crosses? I remember hearing that technically, they're supposed to be triploids.
I've seen a little of this myself with Ed Murray, but the problem with my experience is that prior to my acquisition of Ed Murray, a supposed tet conversion of it was in fairly wide circulation, and there seemed to be a lot of uncertainty as to whether or not any random piece of Ed Murray had been treated. I obtained mine from John Benz, and he said that he had one clump which came to him as "tet. Ed Murray" and an other which was supposed to be "diploid" Ed Murray, but that for him, they both behaved similarly when bred to tetraploids.
The clone I have exhibits no outward signs of conversion, but when I looked at the pollen under a microscope, I saw diploid-size grains, a lot of chaff, some tetraploid-size grains, and a smattering of extra-large grains, maybe 5%. Every few years, I pollinate most of the blooms on Ed Murray with tetraploid pollen, and usually I'll end up with one or two seeds, which, so far, have grown out to be plants which are easily fertile with known tetraploids. I don't see much pollen from my clone (many deformed/shriveled pollen sacs), but when it's available, it's reasonably fertile with tetraploids.
Registration data isn't infallible, however the entry for Thornbird in the NGA database shows 6 tetraploid offspring—some from a tet parent and some from a dip parent. Of these, I only have experience with Norman Lee Hennel, which is quite fertile both ways with tetraploids.
ediblelandscapingsc said:It only had 3 blooms the first was pollinated with Forbidden Fantasy the other 2 with forestlake ragamuffin
admmad said:
If a grower has a diploid version of a cultivar and they also have the tetraploid version of the same cultivar then it is possible to check pollen sizes or various other cell sizes to determine whether the tetraploid version really is tetraploid. Most pollen develops from tissue layer 2 of the growing point. There are three tissue layers in the growing point. A very small fraction of pollen in daylilies develops from tissue layer 1 and none develops from tissue layer 3. So, if the pollen is approximately twice the volume of the diploid plant's pollen (or approximately 30% larger in any linear dimension) then layer 2 of the putative 'tetraploid' plant is confirmed as tetraploid.
However, if one simply has a plant of unknown ploidy then one cannot be certain whether it is diploid or tetraploid by examining pollen or guard cell sizes, etc. The reason is that for the general population of daylilies, diploid cell sizes are not completely separate from tetraploid cell sizes. The larger diploid cell sizes overlap the smaller tetraploid cell sizes.
Basically the only way to be certain a plant is tetraploid (derived from a tet x tet cross or a tet grown from seed) is to do a root squash and chromosome count microscopically and count 44 chromosomes in the cells (with the appropriate controls and internal standards, flow cytometry can provide a valid estimate that the plant has the appropriate amount of DNA to be a tetraploid).
bron said:Thank you Maurice. I drew same to the attention of the AHS, saying it could not have been a parent of itself before it existed. However the President replied that the parent was the plant before it was registered and was an example of 'selfing'. I still thought it not logical, so she suggested I contact the hybridizer.
If you like I can try self pollination of some Tets.
cybersix said:I may go off-topic but why a self cross of one tet daylily is rare? Did I miss some post?
ediblelandscapingsc said:for the past 2 weeks about all I've been able to do self tet crosses because the blooms are getting to be less and less most of which have been on Forbidden Fantasy X Forbidden Fantasy I have about 7 pods now that are self tet crosses.
cybersix said:Thanks Maurice. So I'd better toss the seeds Stella x Stella
admmad said:
No, of course not However, the plants may be smaller than Stella, have shorter scapes and have fewer buds, etc. And they will all be yellow-flowered. If you grow enough seedlings from self-pollinations you may be able to select some that are taller than Stella or that have more buds, etc but the odds are against it being easy.
admmad said:
I am inclined to treat the information about the parentage of Thornbird with skepticism. For the cross to have succeeded then 'Little Grapette' would have to be another diploid that produced unreduced gametes. However, 'Little Grapette' is one of those small-flowered daylilies whose anthers are very close to its stigma in some of its flowers during the flowering season (my observations) and could likely have some self-compatibility (from H. minor ancestry possibly). I suspect that Thornbird's pod parent might be a tetraploid misidentified as 'Little Grapette' possibly 'Little Grape'. Or the supposed diploid 'Little Grapette' was actually a misidentified tet conversion of 'Little Grapette' or partial tet conversion sold as diploid. So I suspect that Thornbird is from tet Little Grapette x Ed Murray or from Little Grape x Ed Murray.
edited to add: Note the parentage of Little Grape:
Little Grape (Durio-D., 1980) height 18in (46cm), bloom 3.25in (8.3cm), season EM, Rebloom, Dormant, Tetraploid, Ruby, wine and grape with dark ruby red wine eyezone and yellow green throat. (sdlg × Tet. Little Grapette)
admmad said:
I have Floyd Cove daylily catalogues that date from the 1990s. This is what Pat Stamile indicated was the parentage of his 'Lavender Memories' in the catalogue that introduced the plant.
Tet. T-738-B (Houdini x Tetra Yesterday Memories) x (Prom Date x Tetra Lavender Dew)
The AHS parentage information in the registration database for 'Lavender Memories' is probably a typographical error introduced at some point in the process - it is incorrect.