I'm sorry to be tedious, but I'm pretty ignorant, and I have a question about the observations in your "Caveat."
Are you saying that, if one selfed a genetically complex hybrid bearded garden iris--one which was fertile both ways-- "successively for several generations" one would or might produce an individual which was identical to the parent in so far as horticultural interest goes, but came true from seed, so that the traditional vegetative mode of propagation, partition of the rhizome, would not be necessary, for one could simply cross at will and sow a line of whatever whenever demand was there, presumptively for years and decades?
I did not think it worked that way. Am I wrong?
Thanks.
AMW
-----Original Message-----
From: gndavis@peoplepc.com
To: iris-species@yahoogroups.com
Sent: Wed, Jan 19, 2011 6:47 pm
Subject: Re: [iris-species] Prairie Iris Article Crossing Species
ï
May the record be gently corrected on triticale ?
The manmade "origin of triticale" breeding model has certain affinities with apparent iris species origin, as the following will hopefully show.
Triticale is a manmade hybrid of triticum (wheat) and rye (secale), thus amphidiploid. It does not involve barley. The first such "primary hybrids" used wheat as the berry parent and rye as pollen parent. The first generation progeny is a uniform F1 hybrid that is almost always male sterile. However, manmade induced tetraploids from the F1 can be converted from amphidiploid ( 2x genomes ) to tetraploid ( 4x genomes ) by doubling with colchicine or other compounds. This will often restore partial fertility and permit perpetuation of the breeding line. In practice, especially in grain crops where optimizing fertility is critical to grain yield; it is necessary to inter-breed these new partially fertile progenies for additional cycles to fully optimize grain yield through favorable recombination and reselection. Further, these resulting fertile families must be selfed to homozygosity if a true breeding inbred line is desired. This is seldom appreciated. As a result, most commercial triticale varieties are many many generations removed from the initial wheat / rye cross.
It is often assumed that 2X diploid chromosome sets from the ancestral sources are represented equally in the final fertile 4X converted line. We have strong historical observations and some genomic data that this is seldom if ever true in triticale and maize wide crosses. I believe the same is true in iris. Since segregation is often impaired in wide crosses, it is probably safer to assume unequal genome representation. Many have reasonably speculated that this is why two or more wide crosses made with the same pair of individual plants can generate distinctly different sets of progenies. Uneven segregation and representation of native chromosomes and genes during recombination is likely cause.
This is a general description of process in triticale that correlates well to some proposed iris species origins and directly to wide cross iris breeding.
CAVEAT: be careful not to confuse vegetative plant propagation of iris plants with seed generations described above. Vegetative propagation simply clones or carbon copies a specifc plant regardless of whether it is a hybrid or inbred. Seed generations on the other hand reshuffle genes each generation. A line must be selfed successively for several generations to become genetically true breeding.
Actually, I doubt there are many true breeding iris. We make a cross, or mother nature makes a cross, and we like it. Presto - since its an iris and easy to vegetatively grow we clone it and circulate it directly.
Even in species iris seeds circulated it is very doubtful if many (any?) are fixed true breeding lines. The phenotypes may be similar, but genotypes are likely still unfixed and can be mined for sheltered recessives and re-shuffled for additional gene re-combinations within the source line.
So, I'm gettin' round to say I believe Charles Jenkins observations noted below.
And also . . . try lactea wiiide-cross with typhifolia. Believe I got a few seedlings with that wide cross a few years ago. They later collapsed in the seedling stage. I should have embryo cultured them in a sterile environment but didn't do it.
irisman646
----- Original Message -----
From: g*@molalla.net
To: i*@yahoogroups.com
Sent: Wednesday, January 12, 2011 10:11 AM
Subject: Re: [iris-species] Prairie Iris Article Crossing Species
ï
Added Note...Charlie Jenkins was a geneticist that work on the triticale wheat in Canada. A cross of wheat and barley.
So I would believe his results as he was very meticulous.
Will
----- Original Message -----
From: r*@embarqmail.com
To: i*@yahoogroups.com
Sent: Wednesday, January 12, 2011 6:36 AM
Subject: Re: [iris-species] Prairie Iris Article Crossing Species
I have been distracted lately trying to fix a problem with the Iris Encyclopedia so I hope I am not saying something that has already been said. Iris lactea has not been tried with many other species in hybridizing. But Charles Jenkins who was geneticist and hybridizer of spuria irises tried it with the spurias. He got very strange results and if it would be anyone but him, few would have believed it, The first generation he got plants that looked no different than the lactea he used. But Charles did an F2 and to his surprise resulted in many of the seedlings being twins out of the same seed. Each twin produced one plant that looked like the lactea and one that looked like the spuria. Charles was a very meticulous scientist and I believe his results but they are certainly remarkable.
If you want to know what things a species has been crossed with there is two sources you can go to. The later SIGNA checklists listed all croses with a species and the Iris Encyclopedia has all of this information also. Much is not formatted well, because I have not finished with all that work, but it is all there I think.
----- Original Message -----
From: g*@sasktel.net
To: i*@yahoogroups.com
Sent: Wednesday, January 12, 2011 1:04:27 AM
Subject: Re: [iris-species] Prairie Iris Article
Hello El,
Did you come up with a list of what will cross with it? I have always wanted to try crossing it with I. missouriensis which it kind of resembles. In truth I think it is worth trying to cross it with anything really. I does set seed quite easily and if you wanted to make sure of a wide cross you would have to protect the cross.
I think BJâs poem has a lot of truth in it for the prairies â cold tonight.
Jim
From: e*@mymts.net
Sent: Tuesday, January 11, 2011 9:25 AM
To: i*@yahoogroups.com
Subject: Re: [iris-species] Prairie Iris Article
Morning Jim and all.
It took me a few minutes to recall which magazine article you're talking about. I do now remember reading that about lactea in your article. You could always get the editor to post one of those corrections.
Interesting that you mentioned lactea though, as just yesterday I was trying to figure out what crosses with it. I got an OP seed pod off mine this past fall, but I'm pretty sure there was only 1 bloom stalk this year. Perhaps it crossed with itself.
El, Ste Anne, MB Z3
From: g*@sasktel.net
Sent: Tuesday, January 11, 2011 1:27 AM
To: i*@yahoogroups.com
Subject: [iris-species] Prairie Iris Article
To all of you who may have read my article I hope you can forgive me for mistakenly putting Iris lactea in the Spuria group. I misread a description of this Iris which lead to such a result. I was hoping someone would take some editing license with the article.
Jim in Saskatoon
