Production of Macrocystis pyrifera (Laminariales; Phaeophyceae) in northern Chile on spore-based culture

Abstract

Since the establishment of abalone farming, there has been an increase in the demand for Macrocystis as a food source. Therefore, the pressure on natural stock has also augmented and the sustainability of the actual harvesting practices has been questioned. In this article, an attempt to farm Macrocystis pyrifera by zoospores in northern Chile is described; initially under laboratory conditions and subsequently by cultivation in the sea. The experiments were executed during 1 year and two different cultivation methodologies were used: a direct and an indirect method. A maximum frond length of 175 cm was reached and 22 kg m −1 of rope was produced after 120 to 150 days of cultivation in the sea. The algae grew under both methodologies, and no differences in algal length and biomass were detected between the two cultivation systems. However, the direct culture method can be recommended for productive and practical reasons.

Production and fate of kelp detritus

“…Kelp is primarily used for human consumption (Rothman et al 2006, Peteiro & Freire 2011, alginic acid extraction (Vasquez 2008, Vea & Ask 2011, and as feed for cultured abalone (Troell et al 2006, Macchiavello et al 2010. Canopy harvesting has increased dramatically in recent decades (Rothman et al 2006, Vasquez 2008, Thompson et al 2010, Vea & Ask 2011.…”

Nutrient uptake efficiency of Gracilaria chilensis and Ulva lactuca in an IMTA system with the red abalone Haliotis rufescens

“…However, the successful development of Macrocystis farming (Westermeir et al, 2006;Macchiavello et al, 2010), currently allows abalone producers to count on fresh biomass. Nonetheless, other problems associated with abalone cultivation have not been noted, and the potential growth of farms and their concentration mainly in bay restricted areas, which possess multiple uses, makes necessary a sustainable plan for expansion in order to avoid environmental conflicts.…”

Macrocystis mariculture in Chile: growth performance of heterosis genotype constructs under field conditions

“…With this scheme, Westermeier et al (2006) reached 80 kg of Macrocystis biomass m 1 of rope within 12 months from the start. This compares favourably with 14.4 kg within 8 months (Gutierrez et al 2006) and 22 kg within 5 months (Macchiavello et al 2010) for traditional mariculture starting from natural spores seeded on ropes.…”

“…The results of our study show that heterosis, jointly with indoor seedling production, can be used to provide favourable stocks of Macrocystis genotypes with features that are apt to increase the productivity and versatility of mariculture enterprises: -Higher biomass production (66 kg m 1 of rope within 4 to 5 months, in contrast to 14.4 kg m 1 after 8 months (Gutierrez et al 2006), and 22 kg m 1 after 5 months (Macchiavello et al 2010) under traditional management) -Faster growth rates, reaching maximum harvest biomass within 4 to 5 months. This speed-up opens the option to produce two harvests per year -Due to genetic homogeneity, crops of a given genotype appear morphologically uniform, and available space can be used to maximum efficiency -Our laboratory-based seedling production by quasiaseptic growth conditions until explantation of seedlings to the sea seems to drastically reduce the buildup of pathogens and fouling -Highly productive genotypes may be selected with specific morphological properties such as haptera hypertrophy (Fig.…”

“…The resulting artificial substrates with juvenile sporophytes are explanted to mariculture installations in the sea (Gutierrez et al 2006;Macchiavello et al 2010). This method has significant disadvantages, mainly the seasonal restriction and quality of natural spore supply and problems to obtain proper inoculation densities.…”