[vhfpmr (OP)]

What's going on here, it looks like the 'winning' shoot kills off all its competitors.
https://www.youtube.com/shorts/6gRBjN9SiTw

[alancalverd]

Entirely sensible. Many plants produce toxins to kill off their competitors  - roses being particularly adept at this. It seems as though exposure to light and air triggers the effect in this case.

[chris]

Nice video and an interesting observation.

Yes, this is possible. Some trees - acer family - release toxins that suppress the growth of rival species, ostensibly to give their own offspring a better chance.

I suppose there are two things possibly happening here with the tomato: one is that the dominant plant does release things locally that destroy the competing plants. The other is that the dominant plant hungrily devours all available nutrients, and water, and the smaller plants cannot compete. So once they run out of supplies from their seed, they perish. Or it could be both.

[alancalverd]

The "competition" model neatly explains the "maze solving" property of slime moulds too. Problem is that it reduces the wondrous concept of intelligence to one of simple chemistry! Very humbling.

[evan_au]

In the real world, once the initial shoot reaches the surface of the soil, it can spread, and shade out all of the lower shoots.
- This video is a bit artificial, in that the underground shoots manage to get some light through the sides of the glass container...

The first shoot to reach the air can transpire, and suck up nutrients from the soil. The other underground shoots can't transpire, and so have a much lower supply of water and nutrients.

[Petrochemicals]

Not from what i remember of growing tomato seeds. Maybe there are some varieties that do.