The invention provides the disclosure of a novel plant/algae/cyanobacteria photosynthesis, biomass production, and productivity pathway involving low carbon dioxide inducible (LCI) proteins. According to the invention, the activity of one or more LCI proteins may be modulated to increase the same under conditions where such proteins are typically repressed. According to the invention, modulation of LCI protein activity was able to increase biomass production by as much as 80% under elevated CO2 conditions. The invention includes methods, and genetically modified plants/algae/cyanobacteria, cells, plant parts and tissues.