|MadSci Network: Botany|
I've never conducted this experiment, nor seen any such experiments. One problem would be the difficulty of generating strong, stable magnetic fields. However, I can make some conjectures about possible impacts.
First of all, it could affect the plant's food production. As you may know, the plant generates energy the same way we do: breaking down glucose and using high-energy electrons to generate adenosine triphosphate (ATP) from adenosine diphosphate (ADP). Magnetic fields could, albeit very weakly, affect the electrons positions. This could upset the electron transport chain and inhibit -- or enhance -- the energy generation.
Something else to think about. It has been shown that certain organisms contain sensory organs to detect magnetic fields. It is speculated that this is how birds know which way is north, for example. It is possible that strong magnetic fields could affect organisms that help polinate the plants, or eat the plants, and thus alter their growth potential.
Finally, it has been speculated -- I don't personally think there's enough evidence yet, but some have speculated -- that electromagnetic radiation can cause cancer. Naturally if this were true, strong magnetic fields could affect the plant's growth quite dramatically.
I hope this has answered your question. Please feel free to contact me with any further questions at Georgia Tech.
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