They're looking at GMing Nitrogenase into plants so that they're no longer limted by the lack of Nitrogen, they're also working on copying C4 photosynthesis int

They're looking at GMing Nitrogenase into plants so that they're no longer limted by the lack of Nitrogen, they're also working on copying C4 photosynthesis into C3 photosynthesis plants so they can more efficiently use CO2. A superior form of photosynthesis isn't easy to imagine, the one we've got seems to use nifty quantum effects to be very efficient, I think about 80%. Earth cycles carbon, there's been a few spells when it has run out of carbon and turned it a snowball, seemingly saved by carbonate rocks being recycled by volcanoes. I think there'll run out of phosphate before then though.