Showing papers on "Kappaphycus alvarezii published in 2003"

Three decades of Kappaphycus alvarezii (Rhodophyta) introduction to non-endemic locations.

Abstract: Given the increase in demand for sustainable livelihoods for coastal villagers in developing countries and for the commercial eucheumoid Kappaphycus alvarezii (Doty) Doty, for the carrageenan industry, there is a trend towards introducing K. alvarezii to more countries in the tropical world for the purpose of cultivation. However, there is also increasing concern over the impact exotic species have on endemic ecosystems and biodiversity. Quarantine and introduction procedures were tested in northern Madagascar and are proposed for all future introductions of commercial eucheumoids (K. alvarezii, K. striatum and Eucheuma denticulatum). In addition, the impact and extent of introduction of K. alvarezii was measured on an isolated lagoon in the southern Lau group of Fiji. It is suggested that, in areas with high human population density, the overwhelming benefits to coastal ecosystems by commercial eucheumoid cultivation far outweigh potential negative impacts. However, quarantine and introduction procedures should be followed. In addition, introduction should only take place if a thorough survey has been conducted and indicates the site is appropriate. Subsequently, the project requires that a well designed and funded cultivation development programme, with a management plan and an assured market, is in place in order to make certain cultivation, and subsequently the introduced algae, will not be abandoned at a later date. KAPPAPHYCUS ALVAREZI

In vitro somatic embryogenesis and regeneration of somatic embryos from pigmented callus of Kappaphycus alvarezii (doty) doty (rhodophyta, gigartinales)

Abstract: In vitro somatic embryogenesis and regeneration of somatic embryos to whole plants through micropropagules was successfully demonstrated from pigmented uniseriate filamentous callus of Kappaphycus alvarezii (Doty) Doty in axenic cultures. More than 80% of the explants cultured on 1.5% (w/v) agar-solidified Provasoli enriched seawater (PES) medium showed callus development. The callus induction rate was consistently higher for laboratory-adapted plants. The excised callus grew well in subcultures and maintained its growth for prolonged periods if transferred to fresh medium in regular intervals. Some subcultured calli (<10%) did undergo transformation and produced densely pigmented spherical or oval-shaped micropropagules (1–5 mm in diameter) that subsequently developed into young plantlets in liquid PES medium. The micropropagule production was further improved through somatic embryogenesis by a novel method of culturing thin slices of pigmented callus with naphthaleneacetic acid (NAA) or a mixture of NAA and 6-benzylaminopurine. Transfer of embryogenic callus along with tiny somatic embryos to liquid medium and swirling on orbital shaker facilitated rapid growth and morphogenesis of somatic embryos into micropropagules that grew into whole plants in subsequent cultivation in the sea. The daily growth rate of one tissue cultured plant was monitored for seven generations in field and found to be as high as 1.5–1.8 times over farmed plants. The prolific somatic embryogenesis together with high germination potential of somatic embryos observed in this study offers a promising tool for rapid and mass clonal production of seed stock of Kappaphycus for commercial farming.

Structural Analysis of Carrageenan from Farmed Varieties of Philippine Seaweed

Abstract: Kappaphycus alvarezii, Eucheuma denticulatum and, more recently, Kappaphycus sp. 'Sacol' variety, are the carrageenan-containing red seaweeds currently farmed in the Philippines. The Kappaphycus sp. 'Sacol' variety is of particular interest to the Philippine seaweed industry because of its improved resistance to 'ice-ice' disease and its fast growing characteristics. Here we report on the detailed chemical analysis of the carrageenan from this species. The native and alkali-modified carrageenans from Kappaphycus sp. 'Sacol' variety were characterized by FT-IR, 1 H and 1 3 C NMR spectroscopy, and constituent sugar and methylation analyses and were compared to those from K. alvarezii, K. cottonii and Eucheuma denticulatum. The three Kappaphycus species contained predominantly κ-carrageenan with low levels of i-carrageenan, methylated carrageenan and μ-precursor residues, while Eucheuma denticulatum contained predominantly i-carrageenan with significant amounts of v-precursor residues. Taxonomic classification of Kappaphycus species based on morphology has proved to be difficult because of their known plasticity. Molecular analysis using the rbcL sequence revealed that the Kappaphycus sp. 'Sacol' variety is most likely a form of K. cottonii.

Circadian changes in relative abundance of two photosynthetic transcripts in the marine macroalga kappaphycus alvarezii (rhodophyta)

Abstract: Circadian regulation of transcriptional gene expression has been shown for a variety of taxa throughout the eukaryotic kingdom and for prokaryotic cyanobacteria but not previously for macroalgae. We reported earlier a strong circadian rhythm of photosynthetic capacity in the red macroalga Kappaphycus alvarezii (Doty) Doty. To determine whether this rhythm is correlated with circadian regulation of steady-state transcript abundance, we analyzed transcripts of genes whose protein products are involved in photosynthesis. Transcript levels of two plastid-encoded operons, one for phycoerythrin α and β subunits and another for RUBISCO large and small subunits, were analyzed under light:dark cycles (LD) and under constant illumination (LL) for several days. Both transcripts exhibited diurnal regulation under LD conditions with maximum transcript abundance during early daytime to midday. Under LL conditions, circadian oscillations of steady-state mRNA abundance were detected for up to three cycles; thus, the analyzed transcripts exhibited diurnal and circadian regulation. Interestingly, peak abundance of the RUBISCO transcript shifted to subjective night under LL. To our knowledge, this is the first report demonstrating that circadian control of steady-state transcript abundance occurs in a macroalga.

Developing the cottonii (Kappaphycus alvarezii) cultivation industry in the Fiji Islands

Abstract: A commercially successful cottonii seaweed [Kappaphycus alvarezii var. tambalang (Doty) Doty] cultivation industry has been established in Fiji. At the beginning of December 1997, the Fisheries Division of the Ministry of Agriculture, Fisheries, Forest and ALTA established a three-year development programme to obtain commercial volumes (1,000 t y ) and establish a relationship with a commercial partner which would then take over purchasing once commercial volumes were established. The project was funded solely by the government’s Commodity Development Fund, established to promote alternative commodities to sugarcane, the nation’s primary export crop. The project has met the expectations of the government to improve the socioeconomic situation of coastal villagers and improve the coastal environment. At the end of 2000, 80 t mo -1 were produced and purchased by FMC BioPolymer. Annual volumes are scheduled to increase to 3,000 t by 2005. KAPPAPHYCUS CULTIVATION IN FIJI ISLANDS 82 work on, similar to the farm houses found in the Sulu Archipelago of the southern Philippines. This was done without consideration of Fijian traditional culture and their communal activities, meetings and obligations to the village. In addition, with development support by Fiji Fisheries Division, purchasing/marketing provided by the National Marketing Authority and liaisons between the FAO/South Pacific Aquaculture Development Project and the New Zealand Government, seaweed was purchased from individual farmers and sold to FMC Corporation in 1988 and 1989 (Prakash, 1990). However, this collapsed in 1993 for two reasons. First, the marketing agent was unable to ship enough monthly volume to cover overhead costs and secondly, the Fisheries Division was unable to provide adequate technical support to increase volumes. Senior fisheries officers of the Fisheries Division studied the past failures and it was discovered that four important components were necessary to achieve a successful cultivation industry: 1. government support 2. a guaranteed market 3. adequate funding to operate the programme until commercial volumes were achieved 4. competent project design, management and execution. The fourth component includes the use of trained field technicians and understanding the barriers to entry into seaweed farming by the coastal villagers and a plan to lower those barriers. Government support was adequate, with funding through the Ministry of Agriculture, Fisheries and Forestry in excess of US$ 1.5 million over a three-year period. FMC BioPolymer assured a market. The key was assuring good project design, planning and execution. Fortunately, a few exceptionally qualified individuals at the Fisheries Division provided the competent project management. FMC BioPolymer also provided technical support and training of field technicians during cultivation development. During the previous cultivation attempts, seasonal production and environmental data were recorded. This information indicated that good growth occurs during the south-easterly trade winds during April to December. Growth slows in January to March with elevated water temperatures and a change in the wind patterns (Prakash, 1990). The current development project took this into account in designing the development plan.