Fair enough but I do feel like our everyday experience with biology informs this. If you cultivate a certain color of rose and release it into the wild, you wouldn't expect that color to persist, right? Maybe I'm out of touch but I feel like that's intuitive. Maybe the technology is sexy and dazzling and that makes it more difficult to engage critically.

Depends on the plant. I've got two GMO plants in my house right now; glow-in-the-dark petunias (https://light.bio/) and purple tomatoes (https://www.norfolkhealthyproduce.com/). The tomatoes breed true (i.e. the seeds have the gene); the petunias do not and must be cloned via propagation.

Roses, fruit trees, etc. are the latter.

How's the glow on those petunias in pitch black? Those look absolutely amazing and the ad is hilarious enough to make me want to pick some up.

I live in the hills of the Bay Area and the light pollution is too great outside for them to be obviously bright unless it’s been a really nice weather day (the parts that are growing are the parts that glow which is fascinating!). Outside, you can tell they look different than other plants if you are told they are different and you really take the time to look. Inside with all the lights off, they definitely make you say WOW!. They’re similar to the old “Indiglo” watch faces of the 90’s. You will not be able to see them glowing even in dim room lighting, the lights must be off.

All that being said, I am still quite happy with them! They take effort to be observed, but that effort is rewarding since it is such a unique experience. It’s really neat to see a stem glowing one night, which indicates that the next night there will be a new bright flower bud. Also I get a huge kick out of doing everything I can to propagate them, since it is stupidly illegal to do so.

Edit: for something comparable that you are familiar with, I would say it would take 6-8 plants at the size they arrive at to make the equivalent amount of light as a single small tea candle.

In pitch black they're very visible unless you're going immediately from bright sunlight. With 5-10 mins of adjusting it's really something.

The photos on the site are definitely long exposure, but I'm pretty pleasantly surprised in person.

But those aren't really in the wild, right? They're in your garden? If they were left to their own devices and started to breed with wild type tomatoes, and/or were subject to selective pressures for an extended period, they probably would either abandon the gene or discover a niche it was adaptive for?

Glow in the dark petunias sound really cool, I want those.

The point is the gene may or may not be passed down at all.

It's possible my glowing petunia has some sort of advantage - the energy use going into the light might be balanced by attracting bugs at night, perhaps - but its seeds won't ever have the adaptation.

The purple tomato, on the other hand, if more attractive to birds who might eat and spread its seeds, might have more likelihood to spread.

The tomatoes will only breed true so long as they are hand-bred or kept in an environment where no other types of tomatoes are around. And even then mutations will eventually creep in.

Same goes with the bacteria, except you may be talking about days or weeks instead of years.

Tomatoes are largely self-polinating.

Yes, mutations will creep in, but the gene will persist more based on a) can it be passed down to seeds and b) does it infer an advantage in natural selection?

The vast majority of changes made by humans to food plants, mostly through selective breeding, but also through gene editing, do not infer a selective advantage (except toward more human breeding). Big red fat juicy tomatoes are a disadvantage in the wild, where hundreds of thousands of years of natural selection pre-humans produced small, hardy, efficient, easy to maintain fruits.

Just like with pure-bred dogs, if humans suddenly disappeared it would probably only take a few decades for many species to return to muttier wildtypes.

Sure, some gene-editing is to make the plants hardier. Some of those genes would likely remain.

We're getting rather off-topic, though, which is about whether the bacteria in your mouth would be likely to mutate and/or swap genes with other bacteria in your mouth.

One could just eat other fruits, is there some reason the tomato, other than marketing "antioxidants", need be the purple fruit one eats?

Maybe it's a different question. Does the flavour seem mostly the same? A drop in for recipes?

Grapes are for luddites! Seriously though, my grapes are so reliable at cropping compared to tomato plants I think it would be more interesting to engineer grapes to be tomato-like.

The reason I bought it was simply "that's neat". I'm not doing it for health reasons.

Mine aren't mature yet, but the flavor is apparently just a pretty typical cherry tomato.

Interesting, thanks.

Ooh, did you grow your purple tomatoes from seed? I haven't seen any starts in my area yet.

Yeah, I ordered a seed packet.

The petunias came grown in a pot.

It's possible (in a sense the species we see were all the winners of the same process). And it's being proposed to try and push desired traits throughout populations, like disease-spreading mosquitos[1]

1: https://en.wikipedia.org/wiki/Gene_drive