Optimizing the application of selected biostimulants to enhance the growth of Eucheumatopsis isiformis, a carrageenophyte with commercial value, as grown in land-based nursery systems

• Published in: Journal of applied phycology 2020-06, Vol.32 (3), p.1917-1922
• Main Authors: Umanzor, Schery, Jang, Sojin, Antosca, Richard, Critchley, Alan T., Yarish, Charles, Kim, Jang K.
• Format: Article
• Language: English
• Subjects: Algae; Biomedical and Life Sciences; Biostimulants; Carrageenan; Climate change; Climatic conditions; Cultivation; Diameters; Dipping; Ecology; Economics; Exposure; Farms; Freshwater & Marine Ecology; Germplasm; Kelp; Life Sciences; Maxima; Nursery grounds; Performance enhancement; Phytol; Plant Physiology; Plant Sciences; Seaweeds; Shoots; Stock assessment
• ISSN: 0921-8971; 1573-5176
• DOI: 10.1007/s10811-020-02091-7

Eucheumatopsis isiformis Núñez-Resendiz, Dreckmann & Sentíes is a red alga with great economic potential due to its iota-carrageenan content that could serve as a substitute for traditional carrageenan sources (Freile-Pelegrín and Robledo, J Appl Phycol 20:537–541, 2008 ) such as the red alga Kappaphycus alvarezii (Loureiro et al., New Phytol 206:489–492, 2015 ), if it can be reliably and sustainably cultivated in open water. Due to prevailing and changing climatic conditions, it is necessary to retain germplasm and to cultivate this alga in tank systems. To develop the necessary, large volumes of seed stock required for stocking open water cultivation farms, three brown seaweed-derived biostimulants were tested. One of these was manufactured from the kelp Ecklonia maxima , the other two were manufactured from the intertidal fucoid Ascophyllum nodosum . Apical segments of E. isiformis were treated either by dipping or by continuous exposure to the biostimulants, at different concentrations. Growth was assessed every seven days by measuring the maximum length of each segment, number of lateral shoots produced by each shoot, fresh weight, and the maximum diameter. The constant exposure treatment produced a greater number of shoots per propagule with no significant effects driven by any of the biostimulants. Increasing or decreasing the concentration of the biostimulants to improve the performance of the dipping protocol was not effective, as compared with a constant exposure protocol. This study supports the increasing number of research articles related to the positive benefits of using macroalgal-derived extracts as biostimulants to support seaweed cultivation.