Domestication of the microalga Scenedesmus obliquus for biomass feedstock production

To advance a strong and economical biofuels and bioproducts industry, tools are needed for breeding microalgae to improve phenotypes of commercial interest, including biomass yield, culture stability, harvestability, and accumulation of valuable compounds. This project aims to increase biomass feedstock yields by the phototrophic green alga Scenedesmus obliquus by using classical breeding approaches combined with advanced genomics technologies. S. obliquus is an oleaginous alga that can be robustly cultivated in open raceway-type ponds and accumulates valuable carotenoid compounds that can feed directly into established commercial markets. Strain improvement technologies based on inter- and intra-specific whole-genome hybridization will achieve major improvements in biomass yield and carotenoid productivity, anticipated from the synergistic effects of crossing diverse germ plasm cell lines using the sexual recombination approaches available with this alga. Systems biology and genomics approaches will fast-track genetic improvements that enhance biomass yield traits for biofuels and carotenoids production. This phase I effort will demonstrate approaches for inducing mating with sexual recombination for S. obliquus. The team will produce high-resolution marker databases for the haploid strain UTEX 393 and the hybrid diploid strain DOE0152Z. Both algal strains will be cultivated in photobioreactors for baseline data generation and comparison.