Development of techniques for the cultivation of Lessonia trabeculata Villouta et Santelices (Phaeophyceae: Laminariales) in Chile

Abstract

Large quantities of brown algae have traditionally been exported from Chile as a raw material, of which Lessonia spp. has amounted to over 130 000 tons annually since 1995. To the export demand has recently been added the new demand for high-quality Lessonia spp. as a foodstuff for the expanding abalone culture industry in Chile. The present study is based on efforts to produce significant quantities of Lessonia trabeculata in long-line culture as food for tank-cultured Haliotis rufescens Swainson and Haliotis discus-hannae Ino, which accept it as an excellent source of nutrition. Small sporophytes of L. trabeculata were propagated in the laboratory from reproductive blades harvested by diving near Coquimbo (30°S). The best culture substrate was polyvinyl chloride (PVC) in small pieces, inserted into the nylon cord for final culturing. Enrichment of sea water with agricultural-grade fertilizer produced no differences in growth and development of the Lessonia compared with results obtained using Provasoli medium. Sporophytes 1–2 cm in length cultured on 12-mm cord were transferred to outdoor tanks with circulating sea water and strong aeration where they were outgrown to 15–20 cm length; at this size, they were transferred to a 50-m long line in the ocean. In a 1-year period, individual plants reached up to 1.7 kg in mass, with average values per cord of about 9 kg. Total production from the long line was about 500 kg fresh weight of the alga. In comparative testing, H. discus hannae grew as well on the cultured algae as on naturally occurring L. trabeculata.