Seaweeds of Panay

This practical book on the seaweeds of Panay, Philippines, acquaints and provides information to members of the academe and research institutions, policy makers, fishermen and businessmen regarding the taxonomy, distribution, ecology and economic importance of these resources. It consists of 4 major parts: (1) Introduction, which reviews the literature, habitat, distribution, morphological structure and reproduction; 2) Classification, which describes the classes to which the seaweeds generally belong; 3) Collection and preservation, which explains the procedure used in treatment of specimens; and, 4) Taxonomic list. A glossary is included, covering technical terms used. All species listed and described in this book are macrobenthic and were collected in Panay and Guimaras Islands.Preface -- Introduction -- Classification -- Collection and preservation -- Taxonomic list: Class Chlorophyceae -- Class Phaeophyceae -- Class Rhodophyceae -- Glossary -- References -- Acknowledgement.1st Ed

Gracilariopsis heteroclada as an extractive species in an aquaculture system

The study was conducted within the integrated finfish broodstock facility complex of SEAFDEC/AQD at Tigbauan, Iloilo, Philippines. The broodstock facility has a water recirculating system. The 500-ton capacity broodstock/spawning tanks were stocked with 25 grouper (Epinephelus coioides) and 90 milkfish (Chanos chanos) breeders. Water from the broodstock tanks passes through the sedimentation tank, then through the filter tank before it goes back to the broodstock tanks. The filter tank has an area of 20 m2, a water depth of 25 cm, and a water flow rate of 43 L sec-1 (≈3720 m3 day-1)

Agar yield and gel strength of Gracilaria heteroclada collected from Iloilo, Central Philippines

Seasonality of yield and gel strength of agar from Gracilaria heteroclada was determined. Gel strength was high (510-794 gm cm-2) during early dry season (October-March) and low (43-101 gm cm-2) during the wet season (May-August). A negative correlation exist (P ≤ 0.05) between agar yield and gel-strength

Biomass and reproductive states of Gracilaria heteroclada Zhang et Xia collected from Jaro, central Philippines

Biomass production and reproductive states were investigated to determine the abundance of Gracilaria heteroclada Zhang et Xia at Jaro, central Philippines from March 1990 to February 1991. Biomass of Gracilaria heteroclada was highest in February (45 g/m2) and lowest in July (1.16 g/m2). Plant fertility was seasonal with the highest percentage of carposporphytic and tetrasporophytic plants occurring in January (48%) and in May (64%) respectively. Seawater temperature was significantly correlated with tetrasporophyte occurrence (r = 0.6586) but not with carposporophyte occurrence. There was no correlation of the occurrence of tetrasporophytes or carposporophytes with salinity or rainfall

Growing the reproductive cells (carpospores) of the seaweed, Kappaphycus striatum, in the laboratory until outplanting in the field and maturation to tetrasporophyte

Carposporophytes of the seaweed, Kappaphycus striatum, from the wild were made to shed spores in the laboratory and grown in multi-step culture method until they reached maturity. For each succeeding transfer onto increasingly bigger culture vessels, there was a marked increase in the growth of carposporelings. When plantlets were ready for outdoor culture, they were placed in aquaria and concrete tanks and later moved to the sea in net cage and long-line for grow-out culture. Successfully growing sporelings from carposporophytes in the laboratory until they reach market size seems to depend on the stage of sporelings and environmental factors such as photoperiod and temperature. In this study, carpospore progenies (diploids) also matured into tetrasporophytes and haploid progenies showed resistance to higher temperature

Clonal production of Kappaphycus alvarezii (Doty) Doty in vitro

Micropropagation has proven to be a reliable method to mass produce certain crops. This method also has been applied in macroalgae to produce clones for seaweed farming. Protocols for callus production and shoot regeneration from protoplasts have been established for some seaweed species like Kappaphycus alvarezii. Cells and larger tissues, whether in solid or suspension medium, have been used to propagate clones which were later tested for suitability for farming. Although clonal production was successful, the long duration of culture in vitro limits the production process making the growing of Kappaphycus in vitro an expensive technique to produce clones. In this study, K. alvarezii was grown in vitro to develop a more efficient protocol for the production of clones. Small sections of Kappaphycus were grown in suspension for 1 month under the same temperature, light, and salinity. The type of media, source of explants, length of explants, and stocking density that resulted in the highest growth rate and survival rate were determined. Growth rate of K. alvarezii is significantly higher in media with inorganic nitrogen added than in Grund medium or Ascophyllum nodosum medium only. The appearance of shoot primordia as early as 5 days was observed in media with higher nitrogen concentration. Growth rates of explants approximately 3 and 5 mm are significantly higher than 10 mm sections. Shoots develop significantly faster in explants from tips than sections from older branches. Growth rate of K. alvarezii grown at 0.5, 0.75, 1, 1.25 s 10 mL−1 of medium is not significantly different. This protocol could significantly reduce the (1) time of culture and (2) cost of plantlets production by not using plant growth regulators and formulated media in vitro. Nursery reared plantlets/propagules for farming would be affordable to the stakeholders for sustainability of seaweed production

Growth and carrageenan quality of sporophyte and gametophyte of the commercially important red seaweed Kappaphycus alvarezii

One dilemma facing the farming of the carrageenophyte Kappaphycus is the deteriorating quality of seedstock. Rejuvenating the commercial stocks using spores from reproductive wild parents that are sexually and asexually produced could perhaps restore the traits that are useful for culture. The use of gametophyte and sporophyte (=tetrasporophyte) phases of Kappaphycus alvarezii from spores is explored as a source of seedstock. The growth and physical properties of semi-refined carrageenan extracted from the resulting sporophyte and gametophyte thalli of the same ages were determined. The growth rate of the diploid tetrasporophyte thalli was significantly higher than that of the haploid gametophyte. Gel strength and yield of semi-refined carrageenan from the two life cycle phases were not significantly different, whereas the viscosity was significantly higher in the diploid tissues. Kappaphycus sporophytes were potentially superior to gametophytes as a source of seedstock for mariculture, but problems need to be addressed – including improving the growth rate and reducing the cost of production – before its application could be realized.This study was funded by the Government of Japan Trust Fund (GoJ-TF FS09S2010T) in SEAFDEC/AQD

Growth and agar quality of Gracilaria heteroclada (Zhang et Xia) grown in a filter tank

Gracilaria heteroclada Zhang et Xia was grown in filter tanks to determine the growth, agar quality and uptake pattern of nitrogen and to observe the water quality in recirculating water system with seaweed. Rapid uptake of nitrogen in G. heteroclada was observed within the first 24th of culture. Filling up of the nitrogen pools in the cell may have continued until the fifth day, the plants started to increase in weight, proportionate to the uptake rate of nitrogen duing the experiment. G. heteroclada stocked at 1 kg m-2achieved a specific growth rate (SGR) of approximately 10.4% d-1 during 15d of culture, at total ammonia-nitrogen and nitrite-nitrogen levels of 0.03-0.27 mg L-1 and 0.04-0.19mg L-1, respectively, in the filter tank. Approximately 11% of nitrogen in the water was removed by the seaweed

Improved growth performance of Gracilariopsis heteroclada via short-term nitrogen enrichment

This study examined the effect of short-term nitrogen (N) enrichment on Gracilariopsis heteroclada growth and agar quality. Planting materials were soaked in different concentrations of ammonium chloride (NH4Cl) for 6 h. Total thallus N content was highest in Gp. heteroclada enriched in 300 mg l-1 NH4Cl. Growth experiments showed that this enrichment treatment (300 mg l-1 NH4Cl for 6 h) increased the growth of Gp. heteroclada (4.22±0.09% day-1) compared with the control (3.68±0.12% day-1). Pond culture using enriched Gp. heteroclada resulted in high growth rates (6.14±0.50% day-1). No epiphyte growth was observed during either the growth experiment or the pond culture. There were no significant differences between the agar yields of the enriched (3.65±0.36%) or control (3.78±0.18%) Gp. heteroclada. Additionally, no significant differences were detected when the gel strength of the enriched (611±22 g cm-2) and control (587±11 g cm-2) Gp. heteroclada were compared. The results suggest that the short-term N enrichment method could be an alternative culture strategy to increase Gp. heteroclada production and lower farming costs.This study was funded by the AQD/SEAFDEC (5309-TTV-S0912T and 5310-TTV-S0015D)