Branch induction and Tissue growth of a red seaweed Gracilariopsis chorda

Abstract

Abstract

Tissue growth and branch induction of the red seaweed Gracilariopsis chorda have been investigated under various indoor cultural conditions. In this study, partial sequences of 18S rRNA gene, ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene and photosystem II thylakoid membrane protein D1 (psbA) gene were used to identify for the species. To culture the Gp. chorda, optimal conditions for the culture temperature, light intensity, salinity, concentration of various nitrogen and phosphate, chemical preservation, and some biological factors were tested. Branches were produced the mostly at the cultural conditions of 20°C under 10μmol m-2s-1 light intensity on a 16h L : 8h D cycle with 27psu salinity in PES medium. The Gp. chorda showed optimal growth in PES medium at 20°C under 40μmol m-2s-1 light intensity on a 24h L : 0h D cycle with 27psu salinity. Optimal size of propagules usable as seeds was 1cm, and apical part of Gp. chorda was grown rapidly and less density of propagule appeared faster growth of tissues and branch induction. The Gp. chorda showed optimal growth in 50μM of ammonium chloride and 5μM of sodium phosphate. It grows very well in 100ppm of Fish waste and showed higher growth rate when branch induction first. In culture medium, Addition of chemical preservatives of 600ppm of sodium propionate and 230ppm of sodium dehydroacetate showed effective preserving after for the tissue culture.