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Hybridization - influence of parents?

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If there is a hybrid of e.g. a Trichocereus from mother x father plants, does the resulting hybrid derive its physical/biochemical characteristics primarily from the mother or father, equally from both, or from one or the other depending on what the parent plants are? Is there a rule of thumb governing this?

 

Thanks in advance for help on this basic Q!

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Good question. Id like to know the same thing.

 

I had previously thought it was more towards the mother but I don't even know where I got that idea. It could be wrong.

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Genetics is rarely so simple. Some traits can be sex linked, but then you also have such a thing as chromosome crossover. Some traits will be dominant and others recessive. Independent assortment further muddies the issue with hybrids as what one might see as 75% one cultivar and 25% another may in fact have very different ratios or proportions of species/hybrids in it due to that independent assortment. To top that all off you also have co-dominant genes and perhaps even the possibility that when two recessive but different genes are inherited neither may express. Sometimes unique and rare phenotypes can arise that were not seen on either parent. Biochemical characteristics and phenotype may have additional sets of genes that influence them resulting in varying concentrations of phenotypic characteristics and such. 

 

I have heard Zelly talk about how some crosses will give predominantly one phenotype, but a few will still come out a different phenotype. With his Zelly crosses the father was T. grandifloras which has given rise to 100% colored flowers so far when crossed to a white flowered mother. 

 

Serious Hybridizers as a general rule will often cross like this

A x B

B x A

AB x BA

AB x AB

BA x BA

AB x A

AB x B

BA x A

BA x B

 

Mitochondria and chloroplasts are both inherited from the maternal side only. Variegation however appears to be able to pass from either side of the cross as well as result from certain crosses to a lesser or greater degree. It appears that variegation like monstrous or crested traits can be passed on by either side of the cross. The reason for these types of crosses are to lock in various traits that may be missing in the initial f1. Some more interesting information http://www.tucsoncactus.org/html/growing_succulents_in_the_desert_column_May_2010.html

 

Edited by Inyan
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What about BA X AB, Can't forget that one :wink:

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3 hours ago, Halcyon Daze said:

What about BA X AB, Can't forget that one :wink:

Very nice catch indeed my friend. The real truth is that while professional breeders often breed or attempt to breed like this when trying to recover or bring out recessives, many traits may indeed come out in the very first wash such as colorful flowers. in the first filial generation aka f1. However, as things progress to the f2 or backcross you have to grow out many more seedlings than one does in an f1 cross to attempt to bring together and keep together those traits one was after. It is nice when one can see the trait one is after such as colorful flowers as this makes it easy to simply breed color to color thereby increasing ones chances of getting that desired trait. However, other traits that one can not see may be lost in that f1 generation. This is where backcrossing to a known species or cultivar with that trait is important. However, one may also get lucky in breeding your f1 siblings together and get a wide spectrum of possibilities in that grouping as well. When breeding a diurnal flower to a nocturnal flower one comes out with other interesting possibilities as well such as breeding in diurnal flowering times into an otherwise nocturnally flowering species. One might even produce an extended blooming hybrid in which the flower stays open rather than closing.

 

Crosses such as Yowie x Huarazensis may show a very different profile than Yowie x Huarazensis. It is certainly wise from a hybridizers stand point to make such crosses and from a collectors stand point it is very wise to try and grow a few from opposite crosses such as this. However, the real magic and where very large numbers of seedlings will produce much more diversity potentially is a cross such as (Yowie x Huarazensis) x (Huarazensis x Yowie) and the like. Assuming one picks the best two of each variety or seedling one  has and performs sibling crosses as well things could get very interesting very quickly. The trouble again is that some traits are harder to distinguish simply by looking at a specimen.

 

Now, sometimes we see that a hybridizer makes a cross such as Trichocereus pachanoi LER x Zelly2. What are you getting with such a cross? You may think this is easy. Trichocereus pachanoi LER (50%) x Zelly2 50% = 25% scopulicola 25% grandiflorus. The reality is that independent assortment means you could get a seedling that was 50% LER and 50% scopulicola. You may get any percentage of genetics from the Zelly hybrid from either of its parents, but what you can be assured of is getting 50% guaranteed from the LER parent. Then you have chromosome crossover which basically equates to getting new and novel mixes that were not apparent in either parent species or cultivar.  Now, technically this cross is also what is termed an outcross as LER is not a parent, grandparent, etc. to Zelly2. However, other traits for which LER and scopulicola both have in common is one reason such a cross could be made. An added benefit of such a cross is that you are also increasing genetic diversity even more in the resulting seedlings than one would if one simply crossed back to the same clone of T. scopulicola. What might be lost here is any interesting recessives that the cross to T. scopulicola clone might have had hidden. Again, this is another reason for the backcross. Backcrossing to the exact clone in question allows for recessives not seen in that parent as well as those seen to more fully express themselves in the resulting offspring. This is particularly true when those recessives from one parent are heterozygous rather than homozygous or when a compounding effect could occur due to multiple genes having an influence as is often the case when intensities of color vary within a species. You may have one specimen that is pink, one that is red, another dark red, another crimson red, and so on.

 

To illustrate what happens when we are just working with a few genesTrihybridcross.thumb.png.c6dc11fce53da3bda462d5b9d5f04250.png. You can see it readily becomes apparent that one has to grow out more than 2 or 3 seedlings to get a reasonable chance of that 1 special hybrid and even then nothing is guaranteed.

 

Edited by Inyan
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On 25.11.2017 at 5:18 PM, Inyan said:

Very nice catch indeed my friend. The real truth is that while professional breeders often breed or attempt to breed like this when trying to recover or bring out recessives, many traits may indeed come out in the very first wash such as colorful flowers. in the first filial generation aka f1. However, as things progress to the f2 or backcross you have to grow out many more seedlings than one does in an f1 cross to attempt to bring together and keep together those traits one was after. It is nice when one can see the trait one is after such as colorful flowers as this makes it easy to simply breed color to color thereby increasing ones chances of getting that desired trait. However, other traits that one can not see may be lost in that f1 generation. This is where backcrossing to a known species or cultivar with that trait is important. However, one may also get lucky in breeding your f1 siblings together and get a wide spectrum of possibilities in that grouping as well. When breeding a diurnal flower to a nocturnal flower one comes out with other interesting possibilities as well such as breeding in diurnal flowering times into an otherwise nocturnally flowering species. One might even produce an extended blooming hybrid in which the flower stays open rather than closing.

 

Crosses such as Yowie x Huarazensis may show a very different profile than Yowie x Huarazensis. It is certainly wise from a hybridizers stand point to make such crosses and from a collectors stand point it is very wise to try and grow a few from opposite crosses such as this. However, the real magic and where very large numbers of seedlings will produce much more diversity potentially is a cross such as (Yowie x Huarazensis) x (Huarazensis x Yowie) and the like. Assuming one picks the best two of each variety or seedling one  has and performs sibling crosses as well things could get very interesting very quickly. The trouble again is that some traits are harder to distinguish simply by looking at a specimen.

 

Now, sometimes we see that a hybridizer makes a cross such as Trichocereus pachanoi LER x Zelly2. What are you getting with such a cross? You may think this is easy. Trichocereus pachanoi LER (50%) x Zelly2 50% = 25% scopulicola 25% grandiflorus. The reality is that independent assortment means you could get a seedling that was 50% LER and 50% scopulicola. You may get any percentage of genetics from the Zelly hybrid from either of its parents, but what you can be assured of is getting 50% guaranteed from the LER parent. Then you have chromosome crossover which basically equates to getting new and novel mixes that were not apparent in either parent species or cultivar.  Now, technically this cross is also what is termed an outcross as LER is not a parent, grandparent, etc. to Zelly2. However, other traits for which LER and scopulicola both have in common is one reason such a cross could be made. An added benefit of such a cross is that you are also increasing genetic diversity even more in the resulting seedlings than one would if one simply crossed back to the same clone of T. scopulicola. What might be lost here is any interesting recessives that the cross to T. scopulicola clone might have had hidden. Again, this is another reason for the backcross. Backcrossing to the exact clone in question allows for recessives not seen in that parent as well as those seen to more fully express themselves in the resulting offspring. This is particularly true when those recessives from one parent are heterozygous rather than homozygous or when a compounding effect could occur due to multiple genes having an influence as is often the case when intensities of color vary within a species. You may have one specimen that is pink, one that is red, another dark red, another crimson red, and so on.

 

To illustrate what happens when we are just working with a few genesTrihybridcross.thumb.png.c6dc11fce53da3bda462d5b9d5f04250.png. You can see it readily becomes apparent that one has to grow out more than 2 or 3 seedlings to get a reasonable chance of that 1 special hybrid and even then nothing is guaranteed.

 

 

Great post. 

Edited by Evil Genius

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