Cattleya Russell DeMoss - (schroederae x walkeriana) and coerulea genetics

[terryros]

Cattleya Russell DeMoss is a primary hybrid registered in 1992 as (schroederae x walkeriana). This cross was (walkeriana coerulea x schroederae coerulea 'Blue Lagoon'), but neither my plant or maybe any from the cross turned out coerulea. Here is my flower on the currently blooming plant.

The flower is about 12 cm horizontal natural width. I have never gotten more than two flowers. It has pleasant fragrance. It probably is about an equal blend of the two species and has always bloomed without a sheath from the base of a leaf. I understand human genetics fairly well but plant/orchid genetics poorly, but it seems there may be several different coerulea genes amongst the different Cattleya species and at least some must be recessive. If none of the plants of this cross turned out coerulea, this might argue for two different coerulea genes between these two species.

 

[monocotman]

my understanding is that most coerulea genes in cattleyas are very recessive.
Even selfs of coerulea plants do not always produce 100% coerulea plants.
I agree that there are likely to be several different coerulea genes in cattleyas. The gene is likely to be a mutation in one of the pigment pathways. There are many genes involved in these pathways.
Only if your two parents have the identical mutant coerulea gene will you see ‘blue’ flowered progeny.

 

[Ozpaph]

interesting, thanks.

 

[DrLeslieEe]

There may be multiple coerulea genes in one species as well as different multiple gene locations for each species. This means that if the genes do not overlap in the same regions, then the type color appears.