Iris Ann Borlongan1, Hazel Coleen Gaya1, Antoniette Lorain Dimaano1, Franck Hennequart2, Alan Critchley3, Anicia Hurtado4
1College of Fisheries and Ocean Sciences, University of the Philippines-Visayas, 5023 Miagao, Iloilo, Philippines
2Algaia R&D Center 91 rue, Edouard Branly 5000 Laint-Lo France
3Verschuren Centre for Sustainability in Energy and Environment, Cape Breton, Canada
4Integrated Services for the Development of Aquaculture and Fisheries (ISDA) Inc., McArthur Highway Tabuc Suba, Jaro, 5000 Iloilo, Philippines
Eucheuma denticulatum and Kappaphycus alvarezii are two commercially important, cultivated carrageenophytes in Southeast Asia. Large-scale farming of these seaweeds through repeated vegetative propagation and virtual monocropping has resulted in various phyconomic issues. The efficacy of commercial liquid extracts from the brown seaweeds Ascophyllum nodosum (ANE) and Laminaria digitata (LDE) on the direct formation of axes and survival of these two eucheumatoids were examined using tissue culture techniques. Seaweed apical sections (3–5 mm long) were cultured for 45 days at different concentrations of ANE and LDE (i.e., 0.01, 0.1, 1.0, 3.0, 5.0 mL 2L-1), and control (UV-filtered seawater). Results revealed that between the two seaweed liquid extracts, LDE provided better overall performance for E. denticulatum and K. alvarezii in tissue culture. The present study recommends the use of 0.1 mL LDE 2L-1 for optimum results for the tissue culture of E. denticulatum, given the high percent survival (95.3 ± 0.9%), percent formation of direct axes (95.3 ± 0.9%), and their longest length (10.0 ± 0.3 mm) at the end of a typical 45-day culture period, as well as the highest percentage formation of axes at day 14 (88.0 ± 4.9%). 1 mL LDE 2L-1 is recommended in tissue culture of K. alvarezii. Given the effects on survival and direct axes formation and length were different, interpretations should be made with caution. Additional experiments for K. alvarezii are necessary to ensure reproducibility of results in order to confirm the optimum concentration of ANE or LDE that can be applied for mass production of plantlets for out planting purposes. Some of these additional data will be discussed in the presentation.