If you are trying to eliminate a complex trait then random mutagenesis seems like the best approach. Generating delicate functional structures like glochids likely relies on a complex network of genes. The only downside of this approach is that it often damages vital parts of the plant's genome at the same time. And some traits are generated by parallel networks of genes with many redundant elements, so it isnt as easy as knocking out a single essential component. Opuntia are interesting from a genetic perspective since many "species" are in fact hybrid clones that vegetatively reproduce most of the time. Their ploidy levels are all over the place (which is great in a way since cross fertility seems to happen more often than not).
I'm not sure we could build up useful stands of Opuntia in Australia now if we tried. The cactoblastis moth we introduced has become a permanent feature on the landscape and once a decent population accumulates the insect arrives to hollow it out again. It is weird how culture lags behind nature in this regard. Opuntia and some other cacti are still banned like crazy as a result of the trauma we experienced of having half our state covered in prickly pears a century ago (which itself was a result of stunning abuse of the land through tree clearing and overgrazing).
Now I see why Burbank had so much trouble with his breeding program. It also explains the reversion under stress too. What do you mean by random mutagenesis?
Blast the meristems/seeds/pollen with radiation or chemicals to bump up the mutation rate. I think burbank did some of this. For amateur growers it can be tricky since the chemicals or radiation sources are a potentially dangerous to handle. Pollen irradiation is the easiest one to do IIRC.
Mutagenesis might be the way to go. There are places you can send material to have it irradiated; some citrus varieties were develobed this way, like the Star Ruby Grapefruit.
If you are trying to eliminate a complex trait then random mutagenesis seems like the best approach. Generating delicate functional structures like glochids likely relies on a complex network of genes. The only downside of this approach is that it often damages vital parts of the plant's genome at the same time. And some traits are generated by parallel networks of genes with many redundant elements, so it isnt as easy as knocking out a single essential component. Opuntia are interesting from a genetic perspective since many "species" are in fact hybrid clones that vegetatively reproduce most of the time. Their ploidy levels are all over the place (which is great in a way since cross fertility seems to happen more often than not).
I'm not sure we could build up useful stands of Opuntia in Australia now if we tried. The cactoblastis moth we introduced has become a permanent feature on the landscape and once a decent population accumulates the insect arrives to hollow it out again. It is weird how culture lags behind nature in this regard. Opuntia and some other cacti are still banned like crazy as a result of the trauma we experienced of having half our state covered in prickly pears a century ago (which itself was a result of stunning abuse of the land through tree clearing and overgrazing).
Now I see why Burbank had so much trouble with his breeding program. It also explains the reversion under stress too. What do you mean by random mutagenesis?
Blast the meristems/seeds/pollen with radiation or chemicals to bump up the mutation rate. I think burbank did some of this. For amateur growers it can be tricky since the chemicals or radiation sources are a potentially dangerous to handle. Pollen irradiation is the easiest one to do IIRC.
I thought you meant that, but I just wanted to be sure it wasn't just my being crazy too 😁
Mutagenesis might be the way to go. There are places you can send material to have it irradiated; some citrus varieties were develobed this way, like the Star Ruby Grapefruit.
Oh interesting, could you tell me the name of these places?
Because it's not a standard procedure, you have to contact companies that do gamma sterilization and then tell them the strength and duration. This paper lists some past experiments for different plants: https://www.sciencedirect.com/science/article/pii/S2667064X22000343#bib0015
I contacted a company local to me a few years back and it was more than I wanted to pay. I'd rather not deal with CO-60 myself...