I have used back breeding in the past to bring out more of one parent in the hybrids and to get a wider spectrum of hybrids. I seem to have read that back breeding can cause triploid and tetraploid mutations? It has to do with the similar or exact chromosomes interacting once breed. I would like to know more about this process and how it works. Does anyone know or have info on this subject. Am I better off breeding back to the original parents or should I interbreed with the prodigy? I am doing both now but knowing which one has better results will take sometime.
Back breeding??
I know what back breeding involves and such goals you could try and reach using this technique but I know nothing about the mutations. Maybe someone here has some information on the mutation subject.
Now whether to breed back to original parents or with the best specimens depends on what the goal involves. I cannot be one to instruct you since I`m just a hobby gardener but I enjoy discussing this subject I find interesting.
I have recently found a canna seedling lacking in color(imho) but has incredible structure to the blooms that is a pod sibling to another seedling that has incredible color but to me only acceptable structure to the blooms so I have plans to pollinate these two and "wait n see". Neither seedling has the "completeness" of the original parent but each still has a certain set of characteristics that exeeds the original parent so I think I may be on to something.
I would breed back to the original parent if the comparison was similar and the original parent would make the desired outcome more likely.
I know with dogs you can find a certain couple of dogs will turn out a exeptional number of desirable puppies even though neither parents "have it all" as far as desired characteristics in the breed. I`m hoping these two canna seedlings I have my eye on will be a similar experience..but like you say it takes time and patience to know if a combination of parents will turn out the desired results.
Karen
Karen this sounds interesting if your willing to share your photos of your canna I would be interested in seeing them, on or off the list. I also breed cannas and have been working with them for sometime. I have produced a few lime yellow leaf forms as well as some other interesting traits. As for the back breeding I am aware of the potential back breeding can bring out for desired traits. The interesting thing I have found is that it maybe a key in producing plants with extra sets of chromosomes. The process seems very odd. The back breeding causes a mutation were the chromosomes double in each cell producing tetriploids. I am guessing the process happens due to the imbreeding with the hybrids. Unlike breeding with species that can selfpollinate the hybrid pollen is similar but still different causing some upset or mutations. I have looked for a good chart on how the back breeding should be used but so far I have not found any good papers on it. I would think the daylily people have the best and most experience in this area.
Oh, I meant color of the flowers. I do have one lighter leafed canna but the flowers are specie in type. Oh my, next to your collection all my cannas pale in comparison. lol! :)
Check out my garden journal because I`m putting in some of the seedlings from my very first attempts at growing more than a handful this year.
I`m sorta understanding what you mean. You want to bring out a rare combination or number of genes that would be unlikely to happen in nature,result in a mutation and look way cool in the garden.
I would be very much interested in more information presented on the subject and in learning more than just the basics.
Karen
Back crossing with iris doesn't usually change chromozome count unless it was a strange count or different species with different counts to begin with.
Back crossing or crossing siblings is often referred to as your F2 cross. The F2 cross is where you want to grow out a large number of seedlings in hopes of pulling out recessive traits that might not occur in nature or hope for an increase in a quantitative set of genes/traits that your going after. Both crossing siblings and back crossing to both parents is often done by many hybridizers. I have heard of using a plant that is related, but not compatible for a pollen donor and this can result in haploid plants as often the immature embryo will expel the foreign chromosomes. Sometimes all of the foreign chromosomes are expelled, sometimes only most of them are expelled. Sometimes the haploid embryo will then double on its own without the use or addition of colchicine or some other doubling agent. A lot depends on the plants your working with. The stigma is often the barrier to fertilization with such semi-compatible or non-compatible crosses and simply cutting the style and applying the pollen a little lower in the style can help. Still, if the cross is not meant to be you may find that the pod aborts and you find immature seeds or no seeds at all. A pollen mixture or cocktail can then be utilized sometimes, but again... compatible pollens generally grow faster than non-compatible pollens so you have to go light with the mixture so as to enable all pollen grains to make it to an ovule. Still more importantly, you have to leave enough compatible pollen that the pod does not abort. Or learn how to tissue culture and rescue the embryo that has formed which is also done. Another important thing to keep in mind is the length of the style of the pollen donor. If the pollen donor has a short style you may have to shorten the length of the receiving style to match that of the pollen donor or perhaps even make it a bit shorter. Yeah, I know I didn't really answer your question, but I think I may have given you a few thoughts to work with if your looking to add something new to your plants. I like to think of mutations desirable or undesirable as things that while influenced by genetics and environment... are the result of growing out enough seedlings from a single cross to detect those few that happen and those few that are worth keeping or working with.
Back crossing is often used with species in iris work. One siberian breeder has had good luck crossing half-sibs.
Bwilliam, EricKnight, thanks for the info. I have been doing some breeding back to species with Hosta, one is Pycnophyla, the traits I have been looking for are white back, serrated leaf edge, I have several seedlings that I have accomplished this. another species that I work with is Kikutii. I have other species, but haven't used them yet. one year I collected all I could with the idea that most of the dealers wouldn't have them available any longer because of their being so plain. so if I wanted to do some crosses with them later, I better start collecting before they're gone. Jim