Seedling lacks chlorophyll?

[Shane]

I noticed one of my Astrophytum seedlings looks pretty yellow. Trying to figure out if it's just a phase or if lacks chlorophyll. What do you think?

[greenknight]

Sometimes they green up, but some seedlings are just defective. All you can do is wait and see.

[Hanazono]

The pale seedling on your photo is called "twilight" and weak / short life.
The problem is caused by hybridisation issues normally.
Is your Astrophytum hybrid?

[Shane]

The pale seedling on your photo is called "twilight" and weak / short life.
The problem is caused by hybridisation issues normally.
Is your Astrophytum hybrid?

I don't know too much about the seeds. They were labeled Astrophytum mix and came from cultivation. I'd guess there are hybrids (and hybrid offspring) in there. I'm curious to learn more about what "twilight" is

If this plant is variegated or albino I'd like to save it via grafting

[Hanazono]

It is possible to save the pale seedling by grafting.

The scion will turn to a variegated plant but the life is still short.
The life will be 3~4 years.

Japanese developed various Astrophytum hybrids.
They found forming of high percentage of variegated seedlings with certain parents combination.
The variegation is not true variegation and not clear as like twilight, and so named twilight variegation.

From my experience:
asterias-yellow petals with orange throat
myriostigma-yellow petals

If you crossed Astrophytum with different flower petterns as shown above, high percentage seedlings will be "twilight".

asterias-yellow petals with orange throat
coahuilence-yellow petals with orange throat

The above combination will give less chance of twilight formation.

[Aloinopsis]

I have these twilight seedlings occasionally as well. There's no point in grafting them, they don't last long. They're direct evidence of inbreeding depression. Some cactus species rarely show this level of depression, but Astrophytum do.

[Shane]

Very interesting. Thanks for the info

[Shane]

Hanazono, at what age do you recommend grafting this seedling? It is about 4 months old

[Hanazono]

40 days after germination shows the best success rate of Astrophytum seedling grafting.

4 months old seedling is also alright to graft.

[Shane]

40 days after germination shows the best success rate of Astrophytum seedling grafting.

4 months old seedling is also alright to graft.

Thanks Hanazono. Your knowledge continues to impress me

I'm probably going to graft to perioskopis (because that's what I have), but for the future what stock do you recommend?

[Aloinopsis]

I'm not Frank, but I have been experimenting with grafting to Pereskiopsis for several months or a year, then grafting to a young Ferocactus.

This does work, and it has several benefits because the first graft increases size quickly and is not permanent whereas the second one stabilizes growth and can be permanent.

[Pereskiopsisdotcom]

So far all of the Astrophytum seedlings I've had that have turned out to be variegates have been a bright pink after germination. Most died within a few weeks without grafting. I grafted them to Schlumbergera for a couple of months and then regrafted to Pereskiopsis. They'll go on something more stable like Myrtillocactus in a year.

[Hanazono]

It is alright a twilight seedlings to graft onto a Pereskiopsis stock.
The scion will reach to a flowering size within 2 years if you managed well.
You should regraft it onto permanent stocks such as H. jusbertii or Myrtillocactus
You should regraft it within 2 years old because an older scion reduces the success rate of the grafting.

The scion should be kept in a shady place.
The scion will turn to white colour and die if you kept it in under strong sunlight.

For your reference, I attache a photo, a grafted 2 years old Astrophytum twilight seedlings.
https://cactiguide.com/forum/download/f ... w&id=69140

[Shane]

So far all of the Astrophytum seedlings I've had that have turned out to be variegates have been a bright pink after germination

My Astrophytum seedlings were a rainbow of different colors, including pink, after germination. One in particular was persistently pink. I have no way of knowing if it's the same one (because I repotted all the seedlings when they were attacked by bugs), but it would certainly make sense

Thanks for the picture Hanazono. I understand what you mean now by "The variegation is not true variegation and not clear as like twilight..."

And thanks Hanazono, Aloinopsis, and perioskopisdotcom for the grafting stock recommendations. I still have some Astrophytum seed and growing Astros on grafts might be my next project

[Aloinopsis]

Remember that you can also graft Astrophytum on Astrophytum!

It doesn't necessarily help the growth speed but grafting a variegated plant onto a fully-green plant or grafting Astrophytum asterias to Astrophytum ornatum can make more difference than you might think. I have done it a few times.