In recent years, the Research Institute for Marine Fisheries (RIMF, under the Ministry of Agriculture and Rural Development) has conducted research on restoring seaweed (Kappaphycus alvazezii) seed sources using tissue culture technology. High-quality Kappaphycus alvarezii are selected and evaluated through morphological characteristics, growth rate and the ability to accumulate high carrageenan content and quality to be used as research materials.

Model of preserving high-quality tissue cultured seaweed (1000 m2) in Ca Na area, Ninh Thuan province. Photo: Dinh Muoi.

In 2021, assigned by the Ministry of Agriculture and Rural Development to carry out the project "Research on the application of high technology in seed production and seaweed cultivation technology for high yield and quality of carrageenan in the Central region", Dr. Le Thanh Tung and his colleagues proactively perfected the technology and developed techniques for rapid propagation of seed sources for intensive cultivation of Kappaphycus alvarezii.

From the selected material source, scientists studied the sample, created fibrous callus tissue and then let them form young plants through the process of embryogenesis. The young plants underwent the incubation process and adapted back to the natural environment. Later they could be used as a source of high-quality seeds for intensive farming and production of commercial seaweed. In this way, seaweed seeds in water were regenerated and restored to the quality of the original seed source.

Farmers move Kappaphycus alvarezii seeds out of the Ca Na salt marsh area to avoid hot weather. Photo: Dinh Muoi.

In Ca Na, Thuan Nam, Ninh Thuan province, young seaweed plantlet have been restored and incubated from the beginning of the season in October 2023 to April 2024. The planting area and output of young seaweed plantlet from tissue culture seed sources are increasing day by day, and there exists a demand to move them to coastal areas for commercial cultivation.

MSc. Tran Mai Duc is a member of the project implementation team from Nha Trang Institute of Technology Research and Application, a coordinating unit of the task. He mentions that algae seeds from tissue culture have high quality, good growth ability and often have outstanding disease resistance compared to natural seed sources that have not been selected.

The incubation and propagation period must be carried out in areas with little wind and no fish eating algae to minimize seed loss. Therefore, the research members decide to preserve and develop seed sources in the salt marsh area of ​​Ca Na commune, Thuan Nam district, Ninh Thuan. Currently, over 2 tons of seaweed seeds have grown well in a secured area of over 1000 m2 equipped with floating buoy wire hanging racks.

Farmers are excited to see the seaweed growing well, achieving both high productivity and quality. Photo: Dinh Muoi.

However, keeping young seaweed plantlet in the salt marsh area is no longer suitable considering the recent period. When the temperature increases, the seaweed may turn yellow, become weak, easily degraded and may decrease in quantity. All seeds are therefore moved to the coastal growing area of ​​Son Hai, Ninh Thuan since the climate and weather conditions there are considered suitable for developing an intensive farming model for high-quality young seaweed plantlet. Local farmers often grow young seaweed plantlet from April to September every year.

After two weeks of monitoring, the high-quality tissue culture of Kappaphycus alvarezii is used for the intensive farming model in the Son Hai area grows rapidly again and has a good adaptation level and compatibility for this ecological zone. The seed source from this model is expected to be attentively developed and transferred to households when the seeds reach a relatively high volume to serve as a high-quality source in service of production.

Scientists at RIMF cultivate Kappaphycus alvarezii tissue culture. Photo: Dinh Muoi.

In the Northern region, the Research Institute for Marine Fisheries tests planting young seaweed plantlet in the aquaculture area at Phat Co Island, Ha Long Commune, Van Don District. As for the result, young seaweed plantlet  here has a relatively stable growth rate, completely meeting the quality of raw material for Kappaphycus alvarezii production. However, young seaweed plantlet samples grown in Van Don still achieve less desirable results compared to young seaweed plantlet cultivating models in Nha Trang and Ninh Thuan.

 Source: Nongnghiep.vn