Oncos 2009

[Regelian]

Simon,

the other parent was the tall bearded 'Mary Frances', a medium blue self.  There are quite a few similar crosses currently being made (by myself, amongst others) with tetraploid regelias, such as I. stolonifera and I. hoogiana, crossed with tetraploid tall beardeds.  The idea is to create a fertile family of tetraploids that would have the best qualities of both groups.  I am, also, working on crosses with tetraploid arils and pumila-type beardeds to create a smaller race with similar qualities.

[Sinchets]

That sounds interesting Jamie. I am new to all this- are all the different groups interfertile? Do dwarf bearded  irises cross just as well with Regelias and Oncos?

[Regelian]

Simon,

unfortunately, it is not that simple with the genus Iris.  Mind you, it is a fascinating challenge to create interfertile hybrids, but most of the bearded iris are not interfertile beyond one generation.  If you want, I can explain this more thoroughly through a personal post, but the basics are that we have various chromosome configurations that are only partly compatable.  Not all Iris are diploids, many are tetraploids and of these, some belong to a group know as amphidiploids.  What this essentially means is, diploids may have 8, 10, 11 or 12 pairs of chromosomes, while the tetraploids twice as many.  The amphidiploids are the fascinating part, as the wild forms represent ancient natural hybrids between incompatable parents that have somehow doubled their chromosomes, thus becoming fertile.

An example is I. chamaeiris, which has 40 chromosomes, made up of two sets of different diploid chromosomes.  The theory is that a dwarf diploid, with n=8 as a basic chromosome configuration, crossed with a n=12 species and formed a 20 chromosome hybrid, which would typically be infertile.  Mother nature wasn't finished, here, and the chromosomes doubled to 40. (there are a few other paths to this result)  This gave a configuration of 8-8-12-12 chromosomes, which, due to the balanced pairs of 8 and 12 chromsomes, could perform a successful meiosis, which creates the eggs and pollen.  The hybrids stabilized to a new species and continues reproducing.   (I have over simplified this a bit, to keep the theory clear)

With the arils, oncocyclus have n=10 (2n= 20 chromosomes) and regelia has n=11 (2n = 22 chromosomes).  Interestingly, they will cross on the diploid level and produce fertile off-spring, despite the uneven chromosome pairs.  An oncoregelia typically has 21 chromosomes in the first generation.  Further generations seem to loose the extra chromosome and often stabilize at 20 chromosomes.  What actually happens is not well understood.

The aril-breds are hybrids with arils and other bearded forms.  They may be crosses with SBD or TB and the fertile ones are artificial amphidiploids in most cases, with 44 chromosomes (10-10-12-12).

This all sound like a lot of rules that need to be understood, which of course helps, but it is the exceptions that make things an interesting challenge.  Most SBD hybrids are actually amphidiploids of 40 chromosomes, such as I. chamaeiris.  When they are crossed with a tetraploid onco or regelia, they will tend to produce infertile offspring due to a chromosome imbalance.  There are exceptions, however, which are again poorly understood, but a good reason to try crosses, regardless of how hopeless they may appear on paper.

I hope this lay some groundwork for you.  If you have questions, please let me know.  I'll make a valliant attept to explain what I understand. A cool website to visit is http://www.smcallister.com/ from Sharon McAllister.  Lots of interesting info and pretty pictures, as well!

[arillady]

Jamie one of the seedlings that I planted out yesterday was a cross: Iris pseudopumila x Iris samariae hybrid (yellow form). It did not show any aril on the seed so I am wondering if the bees might have got there first. Will be interesting to see what eventuates - one seedling germinated out of the 17 seeds in the pots. Just after the first opening atumn rains and when I think that we should have followup rain is when I plant out new seedlings. The soil is still warm and they have a chance to grow on a bit. As we don't have severe winters they newly planted seedlings seem to cope well.

[Regelian]

Pat,

actually, as the seed parent is non-aril, seed will not have an aril.  Their development is part of the morphology of the seed parent.  I suspect the off-spring will be difficult to breed with, as they will now have 18 chromosomes (10 aril and 8 SDB), but I am never one to give up.  It will be exciting to see what comes of it.  I'm always amazed at the influence the arils stamp on their hybrids.

[Regelian]

Here are two more arils that bloomed today.  The first is another clone of I. stolonifera from seed, about 2 weeks later thean clone 3.  The second is a seedling from Harold Mathes, an interesting cross between the regelia hybrid Vera and two different MTB, then crossed together.  Rather tall, 3-4 buds (1 branch), large flower and lightly fragrant.

stolonifera Clone 1
(Vera x Radiant Apogee) X (Vera x Heather Hawk) Mathes

[Sinchets]

That's a lovely fall on the second iris, Jamie 
Have you any idea on how long it will be from seed to flower for this kind of hybrid?

[Regelian]

Simon,

as with most Iris, germination is the key.  Once germinated, seedlings may bloom in the next season, but typically 2 years or more.  If one sows the seed directly as it is ripe and a bit green, it will generallly germinate in a few days to weeks, which gives one a jump.

[Sinchets]

Thanks again, Jamie. I had 3 germinations of onco hybrids in a seed bed- the seed was very old- but they have 3 and 4 leaves already- to be honest I was shocked with how quickly the put on so much growth!

[BULBISSIME]

Jamie, your stoloniferas are like jewels !!

[Regelian]

Fred,  thanks, I have to agree with you.  It is my favourite specie.  I am collecting as many clones as I can get my hands on.

Attached is another seedling from Harold Mathes.  This is a F2 cross of a branched aril seedling X Vanity.  An attempt to get the tangerine factor into the aril lines.  It is a pretty flower, but we obviously are not near our goal! .  What I find interesting is the intense yellow of the column and the lime-gold beard.  I have crossed it with 'Pink Pele' to reinforce the tangerine factor, assuming it is there.  I, also, tried its pollen on I stolonifera, to see if it takes.

[Hans A.]

Harold Mathes. 

Harald Mathes 

[Regelian]

yeah, yeah. Just don't tell him I mis-spelled his name!

[BULBISSIME]

Last one for me in the bulb frame, Iris iberica ssp. lycotis Iris acutiloba ssp. lineolata

Many thank's hans, I think I was a bit tired yesterday.... wrong name !! 



   one year more to wait for new flowers ....

[Regelian]

  one year more to wait for new flowers ....

I hear, ya!  Lovely foto of a very pretty flower, by the way