'C4 photosynthesis', as used by maize and sorghum, could greatly boost rice yields, after a decade of slowing improvements Codename: C4 rice project. Mission: to modify photosynthesis in rice to boost crop yields. Duration: 15 to 25 years. This might sound like science fiction, but it is already under way at the International Rice Research Institute (IRRI) in the Philippines, where William Paul …