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Post by Admin on Mar 17, 2022 17:16:32 GMT
It has been nearly 20 years since I registered the first Reverse Intersectional Cross (RIC) cultivar, Reverse Magic in 2002, from the cross (Age of Gold x Martha W.). There has not been a lot said or reported about this very difficult cross in the intervening two decades, with a couple of important the exceptions. The first of these was the extraordinary report by Wolfgang Giesler of Germany of the remarkable intersectional hybrid peony, "Yes We Can" back in 2013, which is believed to be a RIC hybrid, although, the pollen parent remains unknown. Also, around this same time, Bernard Chow from Australia reported a couple of new RIC hybrids (Pink Fairy and Golden Endeavour) from crosses using pollen from various AGHH's on AGLH tree peony hybrids (AGLH x AGHH). The pollen of Pink Fairy has proved to be remarkably fertile and has produced many excellent intersectional hybrids for me, when used on Martha W. However, one of the main issues associated with this difficult cross has been the level of certainty in identifying the resulting progeny as true hybrids, especially at a very early stage based solely on the appearance of the seedling foliage, as can easily be done in the "regular" (IC) cross.
Very recently, I have received information from Bernard and Lucy Chow, regarding their recent progress in the RIC cross, which they have been focusing on in recent years. I am quite anxious and excited to hear more about their progress on this important cross. Hopefully, they will provide us with more details in the coming days in response to this post.
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yangyong
New Member
Posts: 6
What is your main area of hybridizing interest?: More than one of the above
How would you classify yourself as a hybridizer?: Serious
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Post by yangyong on Mar 19, 2022 10:19:26 GMT
Don，When I visited the website of Gießler paeonien nursery, I saw an interesting intersectional hybrid – ‘ Eurasia’ ( www.giessler-paeonien.de/artikel-shop/str%C3%A4ucher/eurasia/#cc-m-product-12333221126). This cultivar was bred by Schulze / Gießler and the marked cross combination is is Paeonia rockii x P. officinalis. Gottlob und Irmtraud Rieck told me that “ Giesslers had a row of P.rockii seedlings, 3 years old. Steffen Schulze visited, was wondering and Wolfgang said: you can take them with you. In Schulzes nursery they grew and he found the intersectional plant. He informed Wolfgang and gave him part of the plant. Schulzes idea was the name ‘Eurasia’ and he registered it. Giesslers said it was a self pollination, a P. mollis was close, sometimes also called P. officials Mollis, this is a strange plant, looks like P. officials”.    ![]() ![]() |
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Post by Admin on Mar 19, 2022 20:48:50 GMT
Thank you for the information regarding Eurasia. One of the other members of our group, Erik Carlson had recently told me about this new reverse cross intersectional (RIC) hybrid as well. The presumed parentage of this new hybrid (p. rockii X p. officinalis) makes this new i-hybrid the progeny of a (2x X 4x) cross, and thus it is expected to be a triploid, similar to nearly all of the other (IC) intersectional hybrids. However, there is one big difference here. Since the double set of chromosomes are all herbaceous, the ratio of the herbaceous to tree peony chromosomes is now reversed compared to regular intersectional hybrids, so that in this case, we have an i-hybrid that is 2/3 herbaceous and only 1/3 tree peony, rather than the other way around. This does, of course, have a major impact on the overall appearance of the offspring compared to what we normally see in the i-hybrids from the (lactiflora X AGLH) cross (which are 1/3 herbaceous and 2/3 tree peony and thus lean heavily towards their hybrid tree peony pollen parents). So, based on its presumed parentage, Eurasia should be expected to resemble its pollen parent much more than its seed parent, as you have already pointed out. It should be made clear here that p. mollis is simply a small form (variety) of p. officinalis and is therefore also a tetraploid.
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yangyong
New Member
Posts: 6
What is your main area of hybridizing interest?: More than one of the above
How would you classify yourself as a hybridizer?: Serious
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Post by yangyong on Mar 20, 2022 8:35:01 GMT
In 2006, Prof. Liangsheng Wang and Prof. Zhengan Liu, my two teachers, found a herbaceous peony with black spots at the base of its petals in the nursery of Dezhong Chen, a famous Chinese P. rockii breeder in Beijing. Finally, the seedling was identified as a hybrid of P. rockii and P. lactiflora through molecular biology and named it 'He Xie'. Chen Dezhong told me that they had carried out the hybridization of P. rockii x P. lactiflora for many years, but they didn't receive the hybrid seed because they were too busy in autumn.The seeds of successful hybridization may be sown as naturally pollinated P. rockii seeds. 'He Xie' has a very low degree of lignification of its stem, and its leaf shape is more like P. lactiflora. It has a single purple red flower. ![]() ![]()    At first, I thought this cultivars is a triploid like other intersectional hybrids, but through flow cytometry, we found that it was diploid like 'Imposible Dream'. |
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rob
New Member
Posts: 5
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Post by rob on Mar 21, 2022 20:44:30 GMT
Hi Don,
would you please tell us more about the intersectionals you obtained from Pink Fairy pollen on Martha WW?
Could you please post some images?
The other question concerns the rationale of these reverse crosses besides the inherent difficulty and rarity of these hybrids.
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Post by Admin on Mar 22, 2022 22:10:21 GMT
Rob, I have produced about 16 - 18 intersectional hybrids using pollen from Pink Fairy on Martha W. As a group, these hybrids do not standout in any way from all of the hundreds of i-hybrids that I have produced over the years. In every way, to my eyes, they seem just like all the others that I have grown or seen. The flowers have varied greatly from one cultivar to another and have spanned the full range from excellent to ordinary, from singles to full doubles and also over a wide range of flower colors. Both the foliage and the stems, as well as the plant and growth habit of these hybrids have all looked like typical (IC) intersectional hybrids. In addition, none have produced any seeds or exhibited any usual degree of fertility. Based on these results, I honestly don't know what to believe about Pink Fairy or about the i-hybrids that it has produced. There are too many different options to consider here. So, until there is more information, such as measurements of the ploidy levels of PF and/or its intersectional progeny, I have chosen, for the moment, to not make any claims for my i-hybrids that I cannot back up with solid evidence. Thus, for now, I am treating them for what they appear to be, which are normal intersectional hybrids that are triploids.
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yangyong
New Member
Posts: 6
What is your main area of hybridizing interest?: More than one of the above
How would you classify yourself as a hybridizer?: Serious
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Post by yangyong on Mar 23, 2022 7:26:16 GMT
Hi Don,
I also have a strong doubts about Pink Fairy. I have seen photos of this cultivar on Facebook. Its stem is highly lignified, more like lutea hybrid, and has good fertility as seed parent or pollen parent when corss with advanced generation lutea hybrids. I tried to buy a Pink Fairy this autumn and analyze its genetic information through molecular biology technology.
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Post by Admin on Mar 23, 2022 14:50:14 GMT
Rob, Continuing to address your questions regarding the rationale for making reverse intersectional crosses. From the hybridizers point-of-view, the ultimate goal is to produce a "new race" of intersectional hybrid peonies that are fully fertile and thus can be easily inter-crossed with each other or back-crossed to their parents on both sides. In other words, they need to become diploids or tetraploids. Until, quite recently, the intersectional hybrids have been trapped in a hybridizers dead-end (F1 generation), with no good or easy way out. This has severely limited these hybrids to a very narrow range of phenotypes, since they are "all" triploids, with the same (2:1) tree peony to herbaceous ratio.
Crosses made in different directions often give very different results, which is especially true when dealing with triploid parents, as is the case here. Since we don't already know which is the best direction out of the deep hole we are currently in, we will need to travel all of the possible roads to find out. This includes each of the four main types of intersectional crosses, (IC, RIC, IBC and RIBC), using both diploid and tetraploid parents on both side of each type of cross.
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