Alba Cattleya Selfing
 

I recently purchased an alba laelia that was a seedling from a selfing. I bought it thinking the blooms would be alba, but then I got to thinking… will the offspring necessarily be alba since this is technically still crossing genetics? Does anyone know how the crossing works with progeny that can weigh in?

It should be yes. It can get a little more complicated if two plants are being bred but If it is a true alba and not just a light color form then it should only produce alba progeny.

Alba is recessive so If it had any dominant alleles to pass on it wouldn't be alba itself. Does that make sense?

The key is what Louis W said, whether it is a true alba.

However, many plants are mis-identified as alba. If there is any pigment in the flower, or on the plant, it is not a true alba. In that case, flowers will likely still be very pale/near alba, but some color will be there.

A typical example is in Laelia anceps. There are a lot of 'white' flowers, where you have to look deep into the closed part of the lip to find the color (dark stripes).

Some well known plants were considered alba, such as Guarianthe skinneri 'Debbie' FCC/AOS (photo below). Only later was the color deep in the lip noticed, so it is actually forma occulata, nor forma alba.

Lastly, the recessive alba/album mutation is not always on the same gene (it can vary from species to species). This is the case for Paph. niveum & Paph. bellatulum; thus, it is impossible to create an album form of Paph. Psyche - except possibly by repeated backcrosses to obtain double recessive forms of both chromosomes.

Since your plant is just a seedling have a look at the root tips and the young growths especially. If there is any pigmentation (usually reddish root tips and pink to purple dots on the young leaves) then you know your plant is not alba. Every part of the plant should be pigment free.

What species/hybrid is it?

It is Laelia sincorana alba. It has been a dream of mine for some time. I reached out to the seller who I got it from, and they said that I should be a true alba as well. It is the cutest plant ever!

Awesome! I'd say you have a near 100% chance of alba in that case.

My goodness, I'd also love to grow a sincorana alba. Can you message me and let me know where you purchased it? I have almost no room left but love sincorana and its hybrids, and I've had my eye out for an alba for quite some time.