Eucheumatoid Farming in India: Current Status and Way Forward for Sustainable Production

Among the economically important red seaweeds, three tropical seaweeds, Eucheuma, Kappaphycus and Gracilaria, collectively account for more than 43% of the total global seaweed production, which was estimated at 35.76 million (tonnes) t (wet) in 2019 with a value of 16 B USD. The Philippines started the cultivation of Eucheuma in early 1970, while Indonesia started in the mid-1980s. The current annual production of Eucheuma and Kappaphycus together is close to 12 M (T fresh weight). In India, Kappaphycus alvarezii cultivation began in 2001, and annual production peaked during 2013 ca. 2000 MT DW (ADGR % 3.3–4.5%). However, after 2013, the seaweed farms were struck with a severe disease, after which the production abruptly decreased to approximately 200 MT dry weight. The market demand for carrageenan in India is approximately 2000 MT yr−1. The Kappaphycus extract was found to be an excellent phyco-biostimulant and is marketed successfully in India. Recently, its inclusion in cattle and aquafeed as a feed additive has also shown improved growth and immunity of the animal, indicating a potential new market opportunity. To meet the growing demand for value-added products from Kappaphycus, efforts are in progress to improve the vigour of the germplasm through biotechnological interventions such as polyploidy, cellular biotechnology and somatic hybridization while developing innovative farming methods for large-scale production in offshore waters. This paper reviews the problems and possible interventions for sustainable farming of eucheumatoid seaweeds in India.