The Algoculture


The algoculture refers to the large scale seaweed culture. In France, the activity relating to macroalgae is concentrated on the Brittany coast.

Two main methods exist for cultivating and / or harvesting seaweeds : the exploitation of existing deposits in the open sea and seaside harvesting. The harvesting is seasonal and highly regulated. The global challenge is to develop production methods to limit the overexploitation of the resource at sea.

If seaweed is widely consumed as food by populations around the globe, it is still very little exploited by multi-sectorial industries. The will of the FAO (Food and Agriculture Organization) is to valorize this marine strategic resource in value-added applications.

To find out more about the global issues of seaweed farming and macroalgae:


WEALSEA thinks of a high tech Algoculture, and selects seaweed strains as “progenitor” at sea to produce more than 1000T / Ha / year of fresh macroalgae. This production is made possible thanks to a strategic value chain and an integrated culture from the selected seaweed strain to the bio-oriented industrial production.


Wealsea – CNRS collaboration in progress

WEALSEA is in the process of establishing a collaborative research project with the CNRS of Roscoff, surrounding itself of seaweeds experts scientists for its fundamental research.

The CNRS, locally recognized under the name of Roscoff biological station (SBR) has been working on seaweeds topics for over 140 years. The Idealg and Genialg programs contribute, among others, to the research on multi-sectorial seaweeds applications. 

The goal of this collaboration is to provide new elite strains for the production of algal biomass and active molecules . This varietal selection will also lead to an improvement in the quantity and quality of production.

Selection of the genetic material

CNRS scientists will carry out phenotyping and genotyping work on algae strains.

The following tests could be carried out: growth tests, reproduction capacity, active molecules content, biotic and abiotic stresses, and characters affecting the stabilization or biorefining stages.

The promising seaweeds strains identified will then be grown under different light, temperature and nutrient conditions to identify ideal growing conditions.

The genetic map of the seaweeds strains will be identified with the aim to master the genome expression of the seaweeds species. A metabarcoding of the algae strain microbiota can be then carried out to determine the genotype / environment interactions in order to understand the algal ecosystem as a whole.

As part of the collaborative work with the Biological Station of Roscoff, the identified strains of interest will be preserved in a Private Algae Bank, making the biological capital of Bezhin Breizh.


At the Roscoff breeding ponds (VDR), the selected seaweeds strains will be reproduced and multiplied in the hatchery-nusery. Following the fundamental research carried out by the CNRS, the scientists at the R&D unit of VDR will undertake the applied research. 


This microscopic level phase makes the sexual reproduction of the seaweeds strains for the development of new and pure individuals (R&D, seed development, preservation in algae bank, domestication).


This macroscopic level phase makes the multiplication of the seaweeds strains by vegetative growth (pure unialgal & monoclonal strain). This will be the last step before transferring the seaweed material to the mass production at the greenhouse.

Uni algal production

Once the strain selection has been made, the challenge remains in controlling the purity of the genetic material. In open seawater culture, seaweeds in ponds could be biologically and chemically polluted by interacting with other algae strain, exudates or other contaminants.

Hence, the main advantage of cultivating in a closed seawater circuit to be able to isolate the genetic material ; and then obtain a homogeneous seaweed culture per tank.