An appraisal on commercial farming of Kappaphycus alvarezii in India: success in diversification of livelihood and prospects

There is an urgent need for diversifying livelihood of low-income artisanal fishermen due to rapidly dwindling fishery resources. CSIR-Central Salt and Marine Chemicals Research Institute takes pride in being first for pioneering Kappaphycus alvarezii cultivation, heralding an era of commercial seaweed farming in India. The invention of liquefying fresh seaweed biomass to obtain two products in an integrated manner, one being a granular residue rich in kappa-carrageenan and the other being sap rich in potash and micronutrients (ca. 2 % w/v), with proven efficacy has provided a boost to commercial farming. The production has been substantially increased from 21 dry tonnes in 2001 to 1490 dry tonnes in 2013 with concomitant purchase value of < 4.5 to 35 Rs kg(-1) (dry). India is fast emerging as important production center in Southeast Asia for K. alvarezii production with estimated 765,000 man-days of employment, having annual turnover of around Rs 2 billion. At present, commercial farming is carried out following three techniques, namely floating bamboo raft, tube net, and longline method of which former two are widely practiced. The cultivation activity is well established in southern state of Tamil Nadu and progressing rapidly to other areas namely Gujarat, Andhra Pradesh, and Maharashtra. The socioeconomic benefits accrued in this project are overwhelmingly positive, but evidence-based policies are required for addressing prevailing environmental issues. The steps toward developing value-added products with niche applications coupled with biotechnological interventions aimed at seed production through tissue culture for developing elite germplasm, etc. could further improve the prospects of taking this project to pan India level. The present review provides a detailed account of developments of commercial farming that has witnessed successful diversification of livelihood consistently for the last 10 years.