Gary Molano1, José Diesel1, Kelly DeWeese1, Scott Lindell2, Sergey Nuzhdin1
1Molecular and Computational Biology, University of Southern California, Los Angeles, CA, United States, 2Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institute, Falmouth, MA, United States
Macrocystis pyrifera (giant kelp), a brown macroalgae, is a keystone species that establishes forests in the subtidal zone, providing habitat for hundreds of different species, including other algae, invertebrates, fish, and mammals. Giant kelp also holds economic value as a major source of alginate, food, and molecules used in pharmaceuticals and cosmetics. Giant kelp also has potential as a feedstock for biofuel production, as it grows quickly and contains little cellulose or lignin. However, the promise of giant kelp as a major economic force is limited due to a lack of global production when compared to other economically important brown macroalgae such as Saccharina japonica and Undaria pinnatifida. While giant kelp domestication efforts have recently begun, present environmental concerns of invasive species and trans gene flow between wild populations and kelp farms have slowed and sometimes prevented the expansion of giant kelp farms. We propose a novel breeding program that leverages the haplodiplontic life cycle of giant kelp that directly addresses these environmental concerns. Using the emerging giant kelp genomic toolkit, we have scanned a germplasm consisting of 550 haploid giant kelp gametophytes for mutations that affect the meiosis pathway. As giant kelp gametophytes can vegetatively propagate under specific culture conditions, we have maintained our scanned genotypes for test crosses of two individuals with mutations in genes involved in meiosis. We are currently growing trial crosses of sporeless giant kelp selected from our germplasm. These findings should be applicable to other species of brown macroalgae in the future.