- we could make a genetically modified truffle fungi which glows in the dark. Now, why would that help? The problem with monitoring the health of your fungi is that most of the body mass of it is in the form of tiny thread like stuff called mycelium. Even if you take a soil sample it is kinda hard to tell the mycelium of the right species apart from the wrong ones. With some species experts can tell them apart under microscope but the only sure way to tell what fungi’s mycelium you are looking at is to DNA sequence it. Which is expensive thus rarelly done. But if you could make your target specie glow under UV light it would make the analysis that much simpler and cheaper. So we could do it more often and thus learn about what factors favour our truffle faster.
- The other option would be to engineer a kind of “immune system” to our truffle species. Basically to make “nanobots” which leave our truffle but kill other fungi. Now how on earth would one do something like that? I would start by trying to modify mycoviruses (the kind of viruses which attack fungi). Many of them are already quite picky about what kind of fungi they infect, so probably that would help us. Bonus points if we can engineer the virus such that it dies out in nature after a few rounds of reproduction so we can minimize the chances of an escape.
Of course both of these ideas are very speculative, scifi level conceptual stuff. :)