James Smith

And the cells kind of around that space, again, have these pattern recognition receptors on their surface that let them detect bacteria getting into the leaf.

If they detect them, then they mount a response, releasing things like reactive oxygen species.

And so, again, that might not work as well.

But a key difference between plants and animals is that plants rely a lot more on physical barriers for defense.

And myrobacteria, by default, would lack the specialized enzymes to break down parts of the plant, which might be necessary for it to move between leaves or to get into the plant vasculature.

So myrobacteria might not be able to get into the xylem or the phloem, which are like the veins of the plant, and then move around it.

So it's kind of unclear whether it will end up causing...

serious harm to plants, I think there's a reasonable chance that it would.

But plant immune systems generally are much less well understood.

Again, some of the top people have looked into this.

Jonathan Jones, who discovered a lot of parts of plant immunity, is one of the co-authors on the paper.

But I think there is more uncertainty here than in the case of animals.

Yeah, that's right.

I mean, it's still possible that they would, to be clear.

So myrobacteria could end up being able to kill lots of plants, including crops.

I think we are going to struggle to rule that out.

One way that this might happen is a common way that bacteria will get into the phloem, which is one of the veins in plants, is through phloem feeding insects.

So the insects kind of have the bacteria in their salivary glands, and then they're feeding on the phloem, which will have sap in it, which is kind of the blood equivalent in plants.

And then the bacteria get from the insect into the phloem.

That could happen if you're having insects that have been infected with mirror bacteria.