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Physiological responses to the hypo-osmotic and temperature stresses of an invasive species, Gracilaria vermiculophylla, were compared to those of the native Atlantic species, G. tikvahiae and G. cervicornis. For the hypoosmotic and lower lethal temperature experiment, a Connecticut (CT) strain of the invasive G. vermiculophylla and a Rhode Island (RI) strain of the native G. tikvahiae were cultivated at combinations of five different salinities (S ¼ 5, 15, 20, 25 and 30) and at five different temperatures (58C, 108C, 158C, 208C and 258C) for 3 weeks. For the upper lethal temperature experiment, two strains of G. vermiculophylla from CT and Portugal, two strains of G. tikvahiae from CT and RI and one Florida strain of G. cervicornis were cultivated at temperatures ranged from 228C to 398C in 28C or 38Cincrements for 14 days. Gracilaria vermiculophylla showed a wide range of temperature (58C–348C) and salinity (5 – 30 S) tolerance; whereas, G. tikvahiae cannot withstand harsher environmental stresses, such as prolonged exposures to salinities of 20 S and temperatures of 108C or 348C. Gracilaria vermiculophylla also grew faster and had higher survival rates than G. tikvahiae or G. cervicornis. These results suggest that the high tolerance and growth capacity of G.vermiculophylla may be responsible for the successful invasion of this alga into Long Island Sound and elsewhere along the east coast of North America.

In a powerful piece about global hunger, Kenneth R. Weiss shows readers the landscape in Dadaab, Kenya, where people are suffering and dying from chronic undernourishment and hunger-related conditions.

Seaweed genetic engineering is a transgenic expression system with unique features compared with those of heterotrophic prokaryotes and higher plants. This study discusses several newly sequenced seaweed nuclear genomes and the necessity that research on vector design should consider endogenous promoters, codon optimization, and gene copy number. Seaweed viruses and artificial transposons can be applied as transformation methods after acquiring a comprehensive understanding of the mechanism of viral infections in seaweeds and transposon patterns in seaweed genomes. After cultivating transgenic algal cells and tissues in a photobioreactor, a biosafety assessment of genetically modified (GM) seaweeds must be conducted before open-sea application. We propose a set of programs for the evaluation of gene flow from GM seaweeds to local/geographical environments. The effective implementation of such programs requires fundamentally systematic and interdisciplinary studies on algal physiology and genetics, marine hydrology, reproductive biology, and ecology.

Today’s fish - dominated seafood consumption pattern cannot be sustained, since supply has shifted from capture to culture (each currently at around 100 million tons/y). Already today, seaweeds (macroalgae) and shellfish dominate mariculture. To prevent crises, wise policies could anticipate this inevitable shift, by promoting seaweed and shellfish production and consumption. The current rate of expansion in mariculture production will inevitably rise in the long run. Eventually, the seafood share in global food supplies, primarily in 3rd world countries, will rise, with the emerging global exhaustion of arable land and freshwater reserves. The sea remains the world’s last food frontier – the only environment that is still available for expansion of food production. A sustainable expansion of seafood culture by orders of magnitude necessitates a balance, as in agriculture, between fed aquatic animals (fish, shrimp…) and extractive plants and animals (bivalves, detritivores). Extractive organisms ameliorate the environmental impacts of the fed animals’ farming, while bringing more income and jobs. Cultured seaweeds, with their biochemical composition and high protein content, can also replace much of the fishmeal in aquaculture diets and provide humanity with nutritious protein.