Use this forum to discuss matters relating to Aeonium, Crassula, Dudleya, Echeveria, Kalanchoe, Rhodiola, Sedum, Sempervium and related species. This is where one posts unknown plant photos for ID help.
I attempted some Aeonium x Echeveria intergeneric crosses. An intergeneric cross between Aeonium and sempervivum already exists, and studies show that the 2 genera are not closely related.
E. purpusorum x A. decorum
E. purpusorum x A. haworthii
E. purpusorum x A. zwartkin
As seen below, the A. haworthii pollen is germinating well on the E. purpusorum stigma. Which shows that these 2 genera must be compatible to some extent. Time will tell if we actually get some seeds.
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Interesting attempt. Pollen will attempt to grow tubes on most stigma surfaces, it's the compatibility of the genomes that I think might be your limiting factor.
I'm sure Aeonium and Sempervivum are more closely related than Aeonium and Echeveria. If a study says otherwise have you got a link so I can read it please?
I don't actually remember where I saw it. But in summary it stated that Sempervivum and Aeonium are hardly related, evolving from different clades. Sempervivums evolved from a group of cold hardy sedums, and the sub-genus Jovibarba (now included as sempervivum) split off 1 million years ago. It stated that the sempervivums are most closely related to the sedums in the petrosedum group (very odd).
I'm not sure how much we can trust DNA sequencing, but those were the conclusions from the study.
Sedum must be polyphylletic - it has groups in America that will hybridise with Echeveria, Pachyphytum and Graptoveria whereas those in the Old World don't seem to be able to.
Sempervivum and Aeonium are certainly very distantly related which makes Surreal Succulents work to produce X Semponium all the more remarkable. I have a plant of 'Sienna' here but waiting for it to get bigger and look more representative before I start a thread.
There are some crosses within the Crassulaceae that seem impossible so perhaps your cross may work, I have my fingers crossed!
After a quick look on JSTOR, I found a couple of articles that were relevant.
The Phylogenetic Position of Eastern Asian Sedoideae (Crassulaceae) Inferred from Chloroplast and Nuclear DNA Sequences
This is a study looking primarily at Asian former Sedum (Hylotelephium, Phedimus etc.) That only sequenced a few Sempervivum and Aeonium. They only sequenced a few species of Sempervivum and Aeonium and while it showed a clear separation, they were still fairly closely aligned.
The only other article that seemed to relate was in the predecessor to the BCSS's journal in 1970 and looked at physical features. Seems to have a similar cladogram though!
GENERIC DELIMITATION IN THE SEMPERVIVUM GROUP - -a Numerical Approach
David Bramwell
On an interesting note, I have both Sempervivum arachnoideum and Aeonium decorum going into flower. And, my freezer is full of Aeonium pollen (blushing beauty, plum purdy, Arboreum var. holochrysum, decorum, zwartkin, etc).
Epiphyte wrote: ↑Wed May 18, 2022 4:53 pm
One of the most soul crushing experiences in my life was when John Trager told me that Echeverias and Dudleyas couldn't be crossed.
Interesting. Has he experimented with it? I've heard of some Echeveria x Dudleya hybrids, but I have no idea how trustworthy they are. Flowers would be needed to tell.
Aeonium2003 wrote: ↑Wed May 18, 2022 11:54 am
my freezer is full of Aeonium pollen (blushing beauty, plum purdy, Arboreum var. holochrysum, decorum, zwartkin, etc).
2 Echeveria flowers pollinated with Aeonium decorum and Aeonium haworthii pollen. Interestingly, the stigmas are beginning to spread, which is a good sign...
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Unfortunately, the local squirrels (which were running around and squealing at each other) decided to knock over the echeveria pot. A few developing seed pods were damaged. Upon closer inspection, (after cutting the pods open), it became evident that there are indeed developing seeds.
I get to the flowers before the pollen develops, cut off the anthers, and the petals. Then spray the stigma thoroughly with water, which removes any pollen which may have possibly gotten on it. Then the flowers are covered. This ought to minimize most self pollination... unless these Echeveria are cleistogamous.
Edit: I do remove the covers when I take pictures... I doubt anything could have pollinated the flowers during that time.
