When does alba/album cancel out color in hybrids?

Slippertalk Orchid Forum

Help Support Slippertalk Orchid Forum:

merc

ST Supporter
Supporting Member
Joined
Jan 24, 2019
Messages
174
Reaction score
258
Location
PNW (WA)
I was hoping someone could explain the if/when/how. For example, Hillsview has a couple brachy/parvi hybrids using album brachys and they explicitly say "we do not expect album for this cross". Whereas, QF recently cranked out a Wossner China Moon x delenatii album cross and from the pics I found the delenatii album was able to white-out the yellow from the Wossner China Moon. How does a breeder know when the album will kick in? I was eyeing a Dollgoldi x bellatulum album cross hoping the bellatulum album would cancel out the yellow from the Dollgoldi, but not sure if this is a total gamble since I have limited space and both Dollgoldi and bellatulum tend to get kind of big.
 

tnyr5

Well-Known Member
Joined
Jul 8, 2014
Messages
1,856
Reaction score
1,134
Location
Pennsylvania, USA
A geneticist (and if I'm misunderstanding any of this, I'd appreciate being corrected) will be able to answer the question in-depth, but in the most basic terms: it doesn't just matter that there's a mutation in a plants chromosome that affects pigment, it matters where on the chromosome it is, what type of mutation, and if the two mutations are compatible. The closest thing you'll get to a guarantee of recessive genes expressing themselves, when the first generation didn't work, is to sib-cross the heterozygous progeny.
Dollgoldi x bellatulum fma. album will not produce any pigment-reduced offspring because only the bellatulum parent carries any recessive gene for color, as far as we know. There have been Dollgoldis made with armeniacum fma. markii, however, and a good breeder would have used that ( don't count on that being the case here unless they specifically said so.) Even if they did, it's still no guarantee that the plant you buy would be alba, in fact I'd say even the best-case scenario chances are slim. Considering that the cross will be tough to bloom to begin with, I'd pass on it if I were you.
 

tnyr5

Well-Known Member
Joined
Jul 8, 2014
Messages
1,856
Reaction score
1,134
Location
Pennsylvania, USA
Funnily enough, your best bet at making a Dollgoldi cross that would wipe the yellow would be to cross Dollgoldi to a standard pink delenatii.
 

eds

Well-Known Member
Joined
Feb 16, 2019
Messages
433
Reaction score
246
Location
Nottingham, UK
A geneticist (and if I'm misunderstanding any of this, I'd appreciate being corrected) will be able to answer the question in-depth, but in the most basic terms: it doesn't just matter that there's a mutation in a plants chromosome that affects pigment, it matters where on the chromosome it is, what type of mutation, and if the two mutations are compatible. The closest thing you'll get to a guarantee of recessive genes expressing themselves, when the first generation didn't work, is to sib-cross the heterozygous progeny.
Dollgoldi x bellatulum fma. album will not produce any pigment-reduced offspring because only the bellatulum parent carries any recessive gene for color, as far as we know. There have been Dollgoldis made with armeniacum fma. markii, however, and a good breeder would have used that ( don't count on that being the case here unless they specifically said so.) Even if they did, it's still no guarantee that the plant you buy would be alba, in fact I'd say even the best-case scenario chances are slim. Considering that the cross will be tough to bloom to begin with, I'd pass on it if I were you.
^ I agree.

The chances are two 'album' (in the widest sense) mutations from different species are unlikely to be the same mutation within the same gene.

We speak about having a gene for various characteristics but the reality is that you have a whole series of coding sections for a characteristic with genes for producing parts of the protein or coding for controlling expression or the assembly of the protein or various other things.

So even two 'genes' from very similar species that are all but identical can have mutations in different parts of the pigment expression that can lead to the same end result but in different ways. This can also happen in the same species if the mutation has arisen more than once.

Cross those two genes and you will get a normal phenotype in the F1 cross as each contributes a normal copy of the other's mutated gene but in the next generation (F2) you will get both mutations being expressed again and a percentage of the plants will express BOTH mutations in a homozygous way. Sometimes plants may not be able to survive with both mutations though which could skew your expected results off.

If they all survive evenly, 7/16 of the F2 would be expected to be album with 1/16 having both mutations as homozygous recessive.

If they are expressed as a recessive gene - they could be dominant or co-dominant! Until you try the cross and flower them you won't know!
 
Top