modernshaman

No the seeds would be slightly different genetically from that mother. They will be very similar however wouldn't be a clone since the DNA would be different.

I have grafted 1 of each cross I had and had a crest with TPM x N1 however I lost it to black rot. The other crosses have yet to go crazy but look amazing so far. I have a little of each mutant with TPQC x TPM (monstrose, crested, monstrose/crest, regular columnar, and one that is completely unorganized) These are all TPQC x TPM This was a small section from one of the two first photos. It looked like a Trichocereus santiaguensis mostruosa or T. bridgesii crest that was spineless at first. I removed it as it was a bottom section that didn't seem to be growing unlike the columnar sections. I believed it would have reverted or just not have grown but continues to grow similar to a bridgesii crest IMO.

Stenocereus pruinosus... there is a cactus ID section

2,4-D has been used by some in tissue culture to induce mutations. Its relatively easy to get access to it as it's sold as a herbicide.

Sounds like it was successful. Firm and greener are good signs theres a good connection.

Toothpick has mold on it

The longer you keep them in high humidity the slower you need to acclimate them to the lower humidity. I keep seedlings in high humidity 2 months, 3 max, than just completely remove the dome at once. The pros of keeping the seedlings in high humidity for a longer time is that the seedlings grow quicker and don't need to be watered as often. The cons of high humidity is longer time (week to a month) to acclimate them (not a really big issue), the seedlings are plump (with time you can undo this), and the seedlings are weaker (since you gave them ideal conditions they were baby'd). I must admit that I abuse most of my seedlings getting near full sun at 3 months old. The seedlings are seriously stunted however growth comes quickly once they get use to the high sunlight. I agree with Spine Collector that the orange is likely high humidity. @ Spine Collector - if you sterilize your soil and the pots are clean you can leave the ziplock closed the entire time since the soil will not die out. HOWEVER if you open the bag you shouldn't keep it closed for long periods since you have allowed mold and bacteria to enter. I air out my seedlings every day or two like you however I use a dome.

I would love to have some.

There are two things that I've noticed that makes or breaks areola grafts are pressure and amount of exposed flesh on the scion (areola). I use a screen stretched over the trichocereus very tight and cut the areola flat so that the skin surrounds the entire areola. The more flesh exposed the more it dries out/shrinks making the graft fail. Your tbm graft looks like it will succeed. The validus graft has a chance of success assuming there is high pressure. Why don't you use a faster stock like mutant suggested it will cut down the pupping time by weeks even months.

Pereskiopsis makes the areola pup the fastest however its possible to graft to any of those cacti. I would choose pereskiopsis first than opt for opuntia as a second selection. You can also use trichocereus sp. however they take longer to pup. Any fast growing cacti would be a good choice. I'm not so sure how rare saguaro seeds are in Australia however they are plentiful here in the US. What is rare are mature specimens (branching) since they take so long to grow. I would graft seedlings over areolas since it's easier. If I'm not mistaken it takes 50 years for the first branch to start.

Those look like 'sun/heat burn' that lots of Trichocereus get. It happens when the cactus suddenly gets high sunlight after a cloudy day or in your case very intense sunlight. The marks will not go away and are permanent however as your cactus grows it will be less noticeable. If they haven't already they may start oozing and than it will callous. (some in the pictures seem to have already calloused) I don't think its black rot like Spine Collector had (notice his doesn't look like a boil/pimple like yours)

Here's an update on the graft. With 2 pereskiopsis the scion seems to be able to handle the extra growth. The scion is much thicker and the areolas are further apart. The scion is 7.5 cm long and around 4.5 cm wide. I'll be attempting a lopho on 2 pereskiopsis to see if the lopho can handle it this weekend. In around a month, just a guess, I'll attempt a peruvian on 4 pereskiopsis. I'm still thinking of a better way of possibly adding more pereskiopsis after the flat graft.

It may be root rot however when this happened to mine a while ago and it was from too much sun. The excess sun caused bleaching I guess. Is it soft? If not I wouldn't worry much.

I believe that hybrids are different than cultivars but Im unsure. I think your right that this is done by nurseries as a form of trademarking/recognition. I think it just becomes accepted once that clone becomes recognized or as the cactus clone spreads physically. I would think that an organization would only be needed to record/document it in cases of reporting and naming a new species... again I could be completely wrong. http://www.cactus-art.biz/note-book/Dictionary/Dictionary_C/dictionary_cultivar.htm