Seaweed breeding programs and progress in eastern Asian countries

The use of seaweeds as human food in eastern Asian countries has a long history, stretching back over a thousand years. However, it was not until the late 1940s that cultivation of seaweeds in near-shore coastal areas began. Due to their location, the Korean peninsula, the Japanese islands and the Chinese coasts share a similar seaweed flora in their coastal waters, and it is not surprising that seaweed species chosen for cultivation, methods of farming and post-harvest processing in these countries have a lot in common. In 2016, the total seaweed production in these three countries reached 16,218,406 t, approximately 53.8% of global seaweed production (FAO). In the course of seaweed farming development in eastern Asia, the development and use of seaweed cultivars have contributed significantly to the seaweed farming industry in terms of improving both the biomass yield and the quality of the food products produced. In this article, the recent development of cultivar-related research and applications practised in Korea, Japan and China are reviewed with particular reference to the key commercial species: Saccharina japonica, Pyropia spp., Undaria spp., Cladosiphon okamurarus, and Nemacystus decipiens. In the past 21 years, 47 certified seaweed cultivars have been used in commercial cultivation in these countries. While much of the development effort has focused on increasing yields, a current emphasis in cultivar breeding programs is to increase the quality of farmed seaweed products. More recently, molecular analyses have been integrated into these programs and have become indispensable tools in the breeding process.